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MPE65 and six other lenses @ 4.8X

 
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morfa



Joined: 12 Oct 2009
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Location: Stockholm, Sweden

PostPosted: Mon Feb 01, 2010 12:50 pm    Post subject: MPE65 and six other lenses @ 4.8X Reply with quote

I've made a comparison between the following lenses at 4.8X


Large version>>

Canon MP-E 65mm f/2.8 1-5x (I'm just calling this MPE65 from now on)
SumRay 50/1.9 (Summar 12cm & Raynox +12)
Leitz Focotar-2 50/4.5
EL-nikkor 50/2.8 (old version), reversed
EL-nikkor 50/2.8N first sample, reversed
EL-nikkor 50/2.8N second sample, reversed
Leitz Milar 40/4.5

Initial notes:

Camera body used: Canon 7D

All but the MPE65 were used on a Nikon PB-6 bellows.

Each test image is stacked from 9 exposures using Zerene Stacker.

I have included three EL-nikkors for two reasons:
1) I wanted to know if there is a difference between the old and the new "N" version
2) It's nice to know how much sample variations plays a part in this kind of test and as it turns out it is far from insignificant.

This composite is showing all lenses at f5.6. If you click it you'll get a larger version where each is scaled down to 2000x1333px. Even at that size you can't make out any differences in terms of resolution but it gives you some idea of how they compare when it comes to white balance and contrast.



18MP FULL RES SAMPLES

MPE65
f4: farm5.static.flickr.com/4065/4309444276_a293a2e171_o.jpg
f5.6: farm3.static.flickr.com/2789/4308707335_3df0f7589b_o.jpg
f8: farm3.static.flickr.com/2725/4309445250_ae9e379873_o.jpg

SumRay 50/1.9
f4: farm3.static.flickr.com/2700/4309448598_50c2f257f5_o.jpg
f5.6: farm3.static.flickr.com/2701/4309449004_b69b8fb706_o.jpg
f8: farm5.static.flickr.com/4015/4309449612_c54856c2ba_o.jpg

Leitz Focotar-2 50/4.5
f4.5: farm5.static.flickr.com/4033/4308704579_7102fb129d_o.jpg
f5.6: farm5.static.flickr.com/4067/4308704949_d6844bde38_o.jpg
f8: farm5.static.flickr.com/4029/4309442526_f1234abce3_o.jpg

EL-nikkor 50/2.8N (sample 1)
f4: farm3.static.flickr.com/2557/4308709429_5f567ecd22_o.jpg
f5.6: farm5.static.flickr.com/4017/4308710209_689f9ed208_o.jpg
f8: farm5.static.flickr.com/4012/4309447988_8dd9ebbef6_o.jpg

EL-nikkor 50/2.8N (sample 2)
f4: farm5.static.flickr.com/4042/4309442812_5c2c735478_o.jpg
f5.6: farm3.static.flickr.com/2542/4308705949_60fc6962e9_o.jpg
f8: farm5.static.flickr.com/4008/4309443646_296cc434b4_o.jpg

EL-nikkor 50/2.8 (old version)
f4: farm5.static.flickr.com/4048/4309440780_e282f45f95_o.jpg
f5.6: farm5.static.flickr.com/4002/4309441144_a9984954ba_o.jpg
f8: farm5.static.flickr.com/4060/4308704237_f050f94f5b_o.jpg

Leitz Milar 40/4.5
f4.5: farm5.static.flickr.com/4030/4308708301_27c6beb36c_o.jpg
f5.6: farm5.static.flickr.com/4043/4308708751_bff4ee33ea_o.jpg
f8: farm3.static.flickr.com/2720/4309446504_5d0053d304_o.jpg

Lighting was provided by a single Nikon SB-24 flash unit (see below). It was set to 1/16th, 1/8th and 1/4th of full power respectively for each of the three aperture settings.

The Milar and the Focotar are both f4.5 at their widest so for these I've used this setting instead of f4. Lighting was the same though so theoretically their "widest" image should look half a step or so darker.

When conducting the test I made the mistake of thinking of the "SumRay" as a f2.0 lens while f1.9 is closer to the truth. Consequently the SumRay yielded slightly overexposed results since the effective aperture was a little bit larger (of course also meaning a little less diffraction).

App for Comparisons
I've built a flash app that makes comparing test images easier by syncing the zooming and panning. It's original purpose is to view stereograms (which explains the anaglyph-button) but it works well for comparisons too.

Example: MPE-65 vs SumRay @f5.6
morfa.se/vu2/index.html?imageOne=http://farm3.static.flic...

MPE-65 @f5.6 vs EL-nikkor @f5.6
morfa.se/vu2/index.html?imageOne=http://farm3.static.flic...

Zoom in and out with the "+" and "-" buttons (keyboard or on-screen) and pan using the mouse or arrow keys.

Click "Change images" and copy and paste from the URL:s above to compare two images of your choice.

(Flash can only juggle 3000x3000 pixels so if the files are larger than that (as in this case) only the top, left 3000x3000pixels of the images are visible)

This app is still to be considered a beta-version!


OBSERVATIONS
One of my main tasks here was to find out how good the venerable Canon MPE-65 is performance-wise compared to other optics.

Before we begin the pixel-peeping let me just say this: as someone most familiar with the Nikon system and not having used the Canon system for real since the analogue nineties I'm very pleasantly surprised. If Nikon keels over tomorrow I can now rest assured that there is at least one viable alternative out there.

The MPE65 oozes quality and is a pleasure to use; it's perfectly solid even at maximum extension. The 7D + MPE65 is a kit that should satisfy most macro junkies out there, myself included.

MPE-65 image quality at 4.8X
For this comparison I didn't have time to thoroughly test the lens over its entire magnification range but of course this is what you need to do if you want the complete picture.

So, does the MPE65 sweep the floor with the competition?
– No. Lets just say that If there is something magical about this lens from an image quality standpoint (as you sometimes are lead to believe) it eluded me in this comparison.

The MPE65 is great when it comes to producing clean, contrasty results with consistent edge to edge performance at wide apertures (f4). At f4 its blacks are blacker than all the other lenses in this test. The micro contrast is also very high and when you put these qualities together the results are very appealing – at least at first glance. You could say that the images appear to have an extra level of clarity, straight out of the camera.

In terms of resolving power it's not better than the competition in this test. And while CA are generally under control the Leitz Milar and Leitz Focotar-2 and to some extent the "SumRay"; are slightly better while the EL-nikkors are slightly worse. CA is only an issue at f4 – at smaller apertures it is insignificant even in the EL-nikkors.

The resolution champion in this test is the SumRay.

MPE-65 @f5.6 vs. SumRay @f5.6
Flash comparison


At f5.6 the SumRay clearly outresolves the MPE-65 (see above). Granted, the SumRay is & "cheating" a little since its effective aperture is slightly wider than f5.6 (perhaps f5.4?) and thereby it is slightly less affected by diffraction. The difference isn't big but not insignificant either since you can make out that the SumRay image is a little brighter. Remember that the flash output is exactly the same in both cases so any difference in effective aperture would correspond to an equivalent amount of brightness difference. Looking at these images it is clear that it is far from a full stop difference but lets compare the MPE65 @ f4 with the SumRay still at the "less than f5.6" setting anyway:

MPE-65@f4 vs. SumRay @f5.6
Flash comparison>>


Here, the MPE65 @f4 to the left gets half the amount of flash output (1/16th) compared to the SumRay (1/8th). So in this case the MPE65 certainly has the benefit of larger effective aperture. Still, resolution-wise the SumRay is on par with the MPE65 or even a little bit better.

Stopping down to f8 takes us further into diffraction territory but the resolution difference is still obvious:

MPE-65@f8 vs. SumRay @f8
Flash comparison>>


In fact, at f8 the Canon has the lowest resolution of all the lenses in this test. Also, at this setting the contrast/clarity advantage this lens showed at the wider settings is completely gone.

The MPE65 is a good performer but at this magnification we seem to be pushing its upper limit. While it has the edge in contrast/clarity at the wider settings this is really only an issue if you want to do a minimum of adjustments in post – a simple levels adjustment would cancel most difference between the MPE65 image and the results produced by the other lenses in this test. Also, at f4 and 4.8X, stacking is almost a must and if you are the kind of photographer who accepts focus stacking as part of your workflow you are unlikely to shy away from a simple levels adjustment.

Subjective performance
Determining which lens performs better is quite often a matter of taste. Take this case for instance:

EL-nikkor @f4 vs. Focotar-2 @f4.5
Flash comparison >>


The EL-nikkor @f4 resolves finer detail than the Focotar-2 consistently throughout the frame. On the other hand, the Focotar-2 is almost completely free from CA whereas the EL-nikkor shows relatively much of it. In a case like this I would pick the Focotar-2 without hesitating, but I can see how others might be less sensitive to CA and always opt for maximum resolution!

Another thing that is often and easily overlooked is sample variation.

Two samples of EL-nikkor 50/2.8 N @f4
Flash comparison >>


This test confirms my suspicion that these two virtually identical lenses behave quite differently at f4; One is clearly better than the other. At this setting the difference between these two samples of six element design lenses is larger than the difference between the "good" sample and the three element Milar 40/4.5. Is one of the EL-nikkors to be regarded as a lemon? I'm not so sure! At f5.6) and f8 they are indistinguishable – well, if anything the "bad" one shows a little less (!) CA.

Some additional thougths and rants
The MPE65 is good but at this magnification you can achieve as good or better results with much cheaper alternatives, especially if you intend to stop down beyond f5.6 or can tolerate a small amount of post processing. The MPE65 is the only lens in this test that offers automatic aperture but this is only a real benefit if you're stopping down and then IQ might not be the best. For handheld shooting at 1:1 – 3:1 the MPE65 seems really nice but frankly I would be surprised if the Micro-nikkor 105/f4 + Raynox diopter wouldn't prove to be as good in most relevant aspects.

I really don't mean to bash the MPE65 but I'd like to point out some weaknesses just to counterbalance the praise this lens often receives (and for the most part deserves). The following crop (shot at 1:1 and f16) shows another less than perfect aspect of this lens:



The straight, six bladed iris of the MPE65 can render out of focus highlights in a rather unattractive way. More often than not this will not be a problem but there are occasions where this kind of OOF highlights can become obtrusive in my opinion. This is especially true if there is a lot of dew drops or very moist, textured substrate in the frame. Apart from being unattractive this sort of highlights can become a problem when stacking. The Summar 12cm has no less than 15 rounded diaphragm blades and even when stopped down all the way its opening forms a perfect circle:



This probably wouldn't be possible with an auto-aperture lens though since the friction between the blades would prevent it from stopping down fast enough. In fact, in cold weather it takes quite a lot of torque to change aperture on the Summar.

If I was a Canon user I would most likely buy the MPE65. It's a unique, flexible and well built lens and it offers a lot of convenience especially if you don't want to lug around a bulky and sensitive bellows unit.

If you are a Nikon macro shooter I don't think the MPE65 should be reason enough for you to change systems. The old Micro-nikkor 105/f4 combined with Raynox diopters offer a great alternative. However, there are other things that Canon does better than Nikon in my opinion: I still think Canon's Live view and Mirror lock up is superior to Nikon's. And I much prefer to be able to set the nominal aperture rather than the effective aperture that Nikon forces you to use (with modern optics).

If I was to pick a winner in this test it would have to be the SumRay. It outresolves the rest and shows only little CA. Not only is it a stellar performer but it is also very flexible: Changing the Raynox +12 diopter for a Raynox +6 diopter gives you an excellent 70/f2.6 (very useful for bugs). With a Raynox +25 diopter you get a high magnification 30/f1.2 (which becomes excellent, stopped down a bit). On its own the Summar 12cm is wonderful for lower magnification macros (below and around 1:1) and portraits. If you can tolerate a fair bit of edge softness you can even use it for landscape work. I have a feeling my beloved Sigma 150/2.8 will have to work to defend its place in my bag the upcoming season ;-)

The Raynox lenses continue to amaze me with their optical brilliance. I rate them as among the finest pieces of glass I've ever used. Quite astonishing considering their price tags! They perform a little bit differently depending on which lens you put them on though so you can't smack them onto anything and expect wonders. For instance I tried the +12 diopter on the Canon 100/2.8 USM macro lens: The results were not bad but nowhere near as good as from the MPE65.

These are my opinions and conclusions. Go ahead and pixel peep the samples and please feel free to disagree with me! And if you do, please tell me – I'd like to hear your opinion!

Test Setup
Basically I used the same setup as described in my last lens test: more info here >>

However, one very significant difference was the lighting setup. This time I've taken measures in order to shade the front elements of the lenses and hereby flare was drastically reduced!

The shading was done by adding a small "snout" around the flash head and (more importantly) a "mask" around the diffuser-cup. Simple but extremely effective! Just compare the contrast from EL-nikkor between this test and the last one I did.



I mounted the MPE65 on the same micrometer controlled linear stage as I used with the bellows:


Here you see MPE65 compared to Zeiss Luminar 63/4.5 (not included in this test) at the same magnification and plane of focus. As you can see there is a significant difference in extension. Anybody here knows the actual focal length of the MPE65 at 5X? This also illustrates another point: a small lens leaves much more room for lighting the subject. Another good thing with small lenses is that they are less likely to scare skittish subjects away.

Considering how small the front element of the MPE65 is, I don't see why Canon couldn't have made the barrel a little slimmer. It doesn't have to look like an endoscope but shaving off a little bit of girth at the front end of the lens would have many benefits:
1) easier to light the subject
2) easier to align the lens correctly without looking through the viewfinder (crucial when you need to work with fast moving subjects)
3) easier to monitor the subject from behind the camera (fat lenses with short WD obstructs the view)
4) easier to get better (=lower) angles with subjects on flat surfaces
5) easier to construct a highly effective lens hood: if the MPE65 had a filter thread the same size as the front element (≈25mm) a 1 cm long cylindrical lens hood would be enough to make a huge difference.
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gmazza



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PostPosted: Mon Feb 01, 2010 1:58 pm    Post subject: Reply with quote

Hi John,

Liked a lot this testing seen also on Flickr, after thinking about results I wonder if you tested this lenses in a high diffraction aperture (something like f/16 to f/20), I know the MP-E only goes to F/16

This is very comon in single frame bug shoots wildlife, so I wonder if the diffraction pair all these lenses at a unique unsharp resolving power of there is advantage of one of them in high f/stops ?
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DQE



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PostPosted: Mon Feb 01, 2010 9:22 pm    Post subject: a thought about testing the MPE-65 at f/8 Reply with quote

Just a late-night thought - in looking up the effective f/stop for the MPE-65 at an indicated f/8, at 5x, I notice that it's effectively f/48. The URLs are below:

http://www.lensrentals.com/rent/canon-mp-e-65mm-1-5x-macro/for-canon

http://files.getdropbox.com/u/754116/MPE-65manual.pdf

Wouldn't diffraction at an effective f/48 be expected to cause quite a lot of image blur?

Is the effective f/stop for the other lenses the same as the MPE-65?

Should these lenses be tested at the same **effective** f/stop instead of the same indicated f/stop? I believe Lord V recommends using an indicated aperture of f/5 for 5x magnification with this lens, due to diffraction-induced image blur. Also, I believe diffraction effects should be the same for all lenses at the same magnification and at the same effective f/stop.

I've personally interpreted the forum enthusiasm for the MPE lens as mostly being associated with its ease of use in hand-held field macro photography (in the style of Lord V and others). Turning the magnification ring to obtain a different magnification is usually judged easier than adding extension tubes, +diopter filters, or bellows under these conditions. For static subjects with tripod-based work, this consideration would probably be much less important, of course.

I hope I haven't misunderstood the purposes and design of your tests.

I really enjoyed studying your summary and reviewing your images. I greatly appreciate the careful experimental technique you've used.
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Charles Krebs



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PostPosted: Mon Feb 01, 2010 9:33 pm    Post subject: Reply with quote

John,

Wow... that's a lot of work. Thanks!

I downloaded some of the full frames at f4 and f5.6 (It's interesting to see f8, but at 4.8:1 it's not an aperture for real use in most situations). My impressions were a little different from yours. I guess I tend to value the edge performance more than many do. For example, when I compared the right upper and lower right corners... these details in particular... :



... my impression is that the SumRay is clearly not as good in these areas as some of the others. Particularly at f4. On a full frame body I suspect this would be even more noticeable. With a detailed subject filling the frame from corner to corner this might be a consideration.

They are all (as you have shown us so often!) very capable of some great shots.
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morfa



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PostPosted: Mon Feb 01, 2010 11:44 pm    Post subject: Reply with quote

gmazza> At this magnification I didn't bother with smaller apertures than f8. This was simply because at this magnification diffraction becomes very high if you stop down further (it is quite pronounced even at f8 ). But it could be interesting to ignore this and just compare them anyway – yu never know if something interesting shows up!

DQE wrote:
Is the effective f/stop for the other lenses the same as the MPE-65?


Yes, I think it should be roughly the same or otherwise the images would differ more in exposure since the flash output, ISO and shutterspeed was identical.

DQE wrote:
I've personally interpreted the forum enthusiasm for the MPE lens as mostly being associated with its ease of use in hand-held field macro photography


For handheld the MPE65 certainly beats any bellows alternative from a usability standpoint. However, I don't think there is much difference in convenience between the MPE65 and say Micro-nikkor 105/f4 + Raynox diopter. The magnification range of the MPE65 is perhaps a little wider (not sure) but personally I don't find it 100% ideal for hand held bug shooting – I'd much prefer 0.5x - 4x.

Charles Krebs wrote:
My impressions were a little different from yours. I guess I tend to value the edge performance more than many do.


Thank you very much for your input Charles! You are right – I didn't pay too much attention to edge performance here and I'm glad you're pointing this out (and I should make a note of this in my copy of this article in my flickr-stream)! As I've mentioned before I haven't found edge performance to be that important to me in the kind of photography I usually do and that's probably why I didn't look so closely for flaws there. However I can see myself using a FF sensor some day and then it can definitely make a difference so I think I should take this into consideration more!
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rjlittlefield
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PostPosted: Tue Feb 02, 2010 12:30 am    Post subject: Reply with quote

John,

I think you have set a new standard for lens comparisons. Very nicely done!

About the point you raised:
Quote:
Anybody here knows the actual focal length of the MPE65 at 5X?

I cannot recall ever seeing this reported.

It could be easily measured by fully extending the lens, measuring its exact magnification there, then measuring its magnification when further extended by say 50 mm of extension tubes. The effective focal length is then (difference of extensions) divided by (difference of magnifications). If you go from 5.1X to 5.9X by adding 50 mm of extension, the focal length is 50/(5.9-5.1) = 62.5.

I would love to see the result. The lens is often described as focusing by extension, but as I read the specs, it's clear that can't be all that's going on because it doesn't extend nearly as much as 4*65 = 260 mm.

--Rik
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mgoodm3



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PostPosted: Tue Feb 02, 2010 8:46 am    Post subject: Reply with quote

The MP-E 65 has a fixed rear element suggesting that it doens't just focus by extension.

Just measuring the distance from the object to the detector and knowing the magnification can give you a rough estimate of the focal length. I think that calculates out to about 40 mm at 5:1.
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lauriek
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PostPosted: Tue Feb 02, 2010 10:07 am    Post subject: Reply with quote

I'm not a Canon shooter so don't have an MPE to hand, but having seen one in the flesh, it simply cannot be fixed focal length because there simply isn't enough space inside it when fully extended to allow a 65mm lens to achieve 5:1 magnification (this would require 65*5mm of extension and it isn't that big... I'd estimate from the size of the thing when extended vs not, that it's focal length at 5:1 is around 40mm.

But I'd love for someone who has one to do the test and let us know. If you really want to treat us, run the test at 1:1, 2:1, 3:1, 4:1 and 5:1 (!) Smile

Morfa thanks for putting in the work to do this, interesting read, I'll come back to this and peruse it at greater length later!
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DQE



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PostPosted: Tue Feb 02, 2010 11:31 am    Post subject: Focal length of MPE-65 lens Reply with quote

The lens design cross-section at 1x and 5x magnification, at this URL:

http://www.canon.com/camera-museum/camera/lens/ef/data/macro/mp_e65_28_1_5.html?p=2

The rear "extension tube" is more than a simple tube - it carries with it some of the many lens elements/groups that the lens contains.

Here's quote from this page: "The optics uses a 3-group floating system, which moves three lens groups independently for focusing. "

Doesn't this complex multi-group, variable magnification lens design make it hard to use simple methods to obtain the focal length vs magnification?

I'm sure my ignorance of lens design is showing here, but I hope the above info and lens cross section is useful to others.
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PostPosted: Tue Feb 02, 2010 12:13 pm    Post subject: Re: Focal length of MPE-65 lens Reply with quote

DQE wrote:
Doesn't this complex multi-group, variable magnification lens design make it hard to use simple methods to obtain the focal length vs magnification?

Not really. For any particular configuration (setting of the magnification ring), the complex collection of refracting surfaces in the real lens ends up being accurately modeled by a much simpler "thick lens" that has only two refracting surfaces.

The added-magnification-versus-added-extension test tells you the focal length of that imaginary thick lens, which is also the effective focal length of the real lens in that particular configuration.

Just plugging that effective focal length into standard formulas like 1/f = 1/o + 1/i will accurately compute how much additional magnification you get by adding arbitrarily more extension behind the lens. If you turn the formulas around and apply them to the front side of the lens, you can also compute how much working distance you will lose as you add extension to get higher magnification. The one thing that you cannot do is to compute working distances from scratch by knowing just the focal length. To get working distances, you also have to know the locations of the principal planes, or equivalently, to know the working distance at some specified magnification and focal length.

Thank you for the links to the MP-E65 lens diagrams [which as of 9/14/2017 are now located at http://global.canon/en/c-museum/product/ef353.html]. Those diagrams make it clear that something complicated is happening inside the lens. To determine exactly what that is would require knowing the exact curvatures and refractive indices of all those elements. Probably the moving elements serve two purposes: 1) to correct for lens aberrations that would otherwise vary depending on magnification, and 2) to change the effective focal length thus allowing a wider range of magnifications from the same change in physical length.

--Rik

[Edit 9/14/2017, provide new link to MP-E 65 diagrams]


Last edited by rjlittlefield on Thu Sep 14, 2017 10:21 am; edited 1 time in total
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Myles_T



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PostPosted: Thu Jun 03, 2010 2:04 am    Post subject: Reply with quote

Hi,

I've just bought the MPE65 + focus rails for my 5D mark II and am determined to get some good shots.

I can see how the diffuser cup would make the lighting less harsh, but I was wondering What's the mask around the diffuser cup for?

I'm also wondering why you don't use a ring flash. Is the light too harsh or not directional enough?
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seta666



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PostPosted: Thu Jun 03, 2010 11:09 am    Post subject: Reply with quote

I first red this review in morpha´s flickr site and was a very good read.
I happen to have the same summar 120mm but my unit needs some refurbishment; the balck paint on the inside covering the elements is peeling of, so I may get internal reflections.
After reding this test I thought of doing a similar experiment with a M42 Industar 50mm 3.5 pancake lens and my raynox close up lenses. The main advantage of the industar over other m42 lenses is the very compact design; the problem is that I do not own the CM-3500 kit and the dcr-250 is not as compact as other raynox lenses
According to my own calculations the resulting focal length would be like this, please correct me if wrong:
Industar 50 3.5 pupil 14.285
Summar 120mm f4.5 pupil 26.7
DCR-250 8 dipoters Fl 125mm
MSN-202 25 dipoters Fl 40mm

50 3.5 + msn-202= 22mm f1.5
1/ (0,02+0,025)=22,22mm/14.285=f1.55

50 3.5 + dcr-250= 36mm f2.5
1/ (0,02+0,008) =35,71mm / 14.285=f2.5

120 4.5+msn-202= 30mm f1.1
1/(0,0083+0,025)=30mm / 26.7 =f1.1

120 4.5+ dcr-250= 61mm f2.3
1/ (0,0083+0,008) = 61,3mm/26,7=f2,29

I also red somewhere that the airgap betwwen lenses also affect the final focal length, I do not know how though

I did some quick test yesterday using the "industray" and the working distance and results were pretty good, consiering the cost of the industar, around 17€ on ebay. Contrast was good and no CAs present whatsoever
If I have time this weekend I will try to do some serious test
Regards
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Victorwol



Joined: 25 Jul 2010
Posts: 2
Location: Alexandria, VA

PostPosted: Tue Jul 27, 2010 9:19 pm    Post subject: Reply with quote

Wondering about the ring flash too, any reason to not use it?

Thanks
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