Your diffuser really isn't doing enough. The lights are so close that the bright spot is not much bigger than the flash heads alone. Most of the diffuser is not getting any light. I suggest using a thinner (and perhaps slightly smaller) diffuser and moving the lights farther away.
Edited to remove repetition with Rik's comment, which I hadn't seen.
just starting out in insect macro with ok results, but....
Moderators: rjlittlefield, ChrisR, Chris S., Pau
Rik, I've suspected the diffraction softening issue for a while. Even when using the lens normally, I have to stop down to at least 5.6 for better sharpness. The flare may have returned somewhat as I was concentrating more on general lighting with flashes than anything else and I removed the lens hood while experimenting with the plates. Other than the objective, which is now on the way, for larger items, I think I'm going to look for another lens in the 20-30mm range, maybe enlarger/ copier or microfische lens.
Lou, I tend to agree and I'm going to try some smaller bowls if I can find them. I'm wondering what would be thinner than the styrofoam that offers similar diffusion?
Lou, I tend to agree and I'm going to try some smaller bowls if I can find them. I'm wondering what would be thinner than the styrofoam that offers similar diffusion?
Lots of people, including me, use thin white paper tents. I like to make a bigger wax paper tent outside the white paper tent for "pre-diffusion". And if the flash head has a zoom or comes with an optional diffuser, I use the widest setting.
Some people here have made diffusers out of white translucent pill bottles.
Some people here have made diffusers out of white translucent pill bottles.
A possible cause for the poor central area. I once had a similar experience but with a much smaller lens - a barely noticeable (to the unaided eye) of a finger-print on the center of the lens. Easily removed with a micro-cloth.
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.
Nikon camera, lenses and objectives
Olympus microscope and objectives
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.
Nikon camera, lenses and objectives
Olympus microscope and objectives
At this point, I am considering either the El Nikkor 50 mm f/2.8 or Olympus 38 mm, based on the results Rik posted and others. Before I ask anything else, Rik, I have one question: Regarding the Olympus 38mm, were your findings based on the normal or macro version of the lens? There's quite price difference and I wanted to be sure.
To the group or Rik, how usable are the above two lenses in the field? Do either or both really need bellows (and a recommendation for low cost but decent bellows would be appreciated), or can I get away with macro tubes?
To the group or Rik, how usable are the above two lenses in the field? Do either or both really need bellows (and a recommendation for low cost but decent bellows would be appreciated), or can I get away with macro tubes?
The 38mm Olympus lens one Rik was using would have been the "auto" f/2.8 Macro Olympus - there were two non-auto, macro lenses which are NOT the same.
If you want to work up to around 4x, then the 6 element (f/2.8) enlarger lenses are good value - EL Nikkor, Schneider Componon M and others.
The problem with all of them is that the best apertures are too small - you'll be working with effective apertures well over f/20, which will be noticeable if you look for it. For less demanding applications, they're fine.
Above that magnification range, look at microscope objectives.
See the FAQ: How do I get a bit more magnification?
Tubes are OK - you always have to pay attention to flocking to reduce reflections.
[Edit - goof removed]
If you want to work up to around 4x, then the 6 element (f/2.8) enlarger lenses are good value - EL Nikkor, Schneider Componon M and others.
The problem with all of them is that the best apertures are too small - you'll be working with effective apertures well over f/20, which will be noticeable if you look for it. For less demanding applications, they're fine.
Above that magnification range, look at microscope objectives.
See the FAQ: How do I get a bit more magnification?
Tubes are OK - you always have to pay attention to flocking to reduce reflections.
[Edit - goof removed]
Last edited by ChrisR on Wed Feb 10, 2016 2:45 pm, edited 1 time in total.
Chris R
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rjlittlefield
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I confirm ChrisR's comments. My Olympus 38 mm is the one described at http://www.alanwood.net/photography/oly ... 38-28.html. For another comparison of various lenses at higher magnification, see http://www.photomacrography.net/forum/v ... 1022#51022 and the follow-up (next page of same thread) at http://www.photomacrography.net/forum/v ... 1130#51130. I think that last link has particularly good info because of its discussion of various tradeoffs.
--Rik
--Rik
Thanks, Rik. I read the comparisons with interest and I'm happy to see that the objective seems to win nearly every time. I also linked to the info on the Olympus. It seems there are different versions and vary widely in price on that special auction site. Ones similar to the one you compared were generally $300+, but item 322002709763 is different and much less costly, but whether it is in the same optical category I don't know. I notice the site you linked me to had a "variations" section, and that ePay item starting off with "103...".
Chris, my main purpose here would be something for field use. Actually, what I have may already be suitable once I increase the zoom from the 18mm now to up to 55mm. I doubt hand holding that I'd be going much more than 1:1 or 2:1, maybe 3-4:1 with a tripod. I just came across some reviews on a Venus 60mm that allows up to 2:1 and more with extension tubes. Pricey for my budget though, but intriguing.
Chris, my main purpose here would be something for field use. Actually, what I have may already be suitable once I increase the zoom from the 18mm now to up to 55mm. I doubt hand holding that I'd be going much more than 1:1 or 2:1, maybe 3-4:1 with a tripod. I just came across some reviews on a Venus 60mm that allows up to 2:1 and more with extension tubes. Pricey for my budget though, but intriguing.
ctron , sorry, it appears there WERE ordinary, non macro, 38mm Zuikos.
There were a couple of variants of the f/3.5 macro (4 element, less good), then the expensive f/2.8 291641824101. That one is priced "optimistically" I think.
In the field, unless you're stacking, you'll be stopped down some, making things hard to see. The Venus doesn't have an auto diaphragm, which would put me right off it.
Regular macros with auto diaphragm go to 1:1, and they can be stretched with close-up dioptres or tubes.
A 10x objective on a 100mm macro gives you a great 5x..
There were a couple of variants of the f/3.5 macro (4 element, less good), then the expensive f/2.8 291641824101. That one is priced "optimistically" I think.
In the field, unless you're stacking, you'll be stopped down some, making things hard to see. The Venus doesn't have an auto diaphragm, which would put me right off it.
Regular macros with auto diaphragm go to 1:1, and they can be stretched with close-up dioptres or tubes.
A 10x objective on a 100mm macro gives you a great 5x..
Chris R
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rjlittlefield
- Site Admin
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To clarify... The Olympus bellows lenses do have auto diaphragms, but only when used with the Olympus auto bellows and dual cable release, and in conjunction with a camera that has an old style shutter release button that can accommodate a mechanical pin-type cable release. Unfortunately that rules out every DSLR that I know. It looks feasible to modify an Olympus auto bellows to install an electronic cable release switch driven by the diaphragm control, but I've never pursued that much beyond an idle thought.Lou Jost wrote:Note that the enlarger lenses don't have auto diaphragms either, and would be nearly impossible to use in the field handheld. Same with bellows lenses.
--Rik
Chris, I take it then that the one I mentioned wouldn't be suitable 
. Too bad, but I'm glad I asked.
Yes, I'm counting on the Nikon objective, when it arrives for use from 5-10x with my two telephotos and in controlled settings. I was just looking for something to fill in the gap and for outdoors, either hand held or sometimes tripod.
Lou, thanks for the info. I sort of surmised their outdoor unsuitability as I didn't see many live action photos after a search. Too bad.
So, if we rule out bellows and enlarger lenses, what does that leave for outside (besides that well regarded 65mm Canon which is only a dream for me to own)?
. Too bad, but I'm glad I asked. Yes, I'm counting on the Nikon objective, when it arrives for use from 5-10x with my two telephotos and in controlled settings. I was just looking for something to fill in the gap and for outdoors, either hand held or sometimes tripod.
Lou, thanks for the info. I sort of surmised their outdoor unsuitability as I didn't see many live action photos after a search. Too bad
. So, if we rule out bellows and enlarger lenses, what does that leave for outside (besides that well regarded 65mm Canon which is only a dream for me to own)?
They might be very good - we don't know! It's unlikely, because a reversed lens is only using small section in our macro application, of the angle it was originally designed for. Compromises will have been made.
I suggest you use your recent experience on lighting & whatnot, and retry the 50mm lens reversed on the 135 and 200mm teles. Check for the best aperture onthe front lens, then try a stack..
Is there an alternative to the CANON MP-E? I bought a Canon.
I suggest you use your recent experience on lighting & whatnot, and retry the 50mm lens reversed on the 135 and 200mm teles. Check for the best aperture onthe front lens, then try a stack..
Is there an alternative to the CANON MP-E? I bought a Canon.
Chris R
centipede
Based on NikonUser's suggestion last week to check rotting/ decaying wood for carpenter ants, I went on a search. What I found was not ants, but a small, roughly 1" centipede within a decaying log so I grabbed it and decided to try it out tonight.
I must say that I am surprised at the detail I was able to acquire from the stack. Since the centipede is much larger than the ant, I increased the reverse lens zoom from the 18mm I had for the ant, to 55mm for this. At that level, I was able to fit about half of the centipede across the field. Attached it the result, about 30 frames stacked at 2.5:1. It was MUCH easier to get the flashes to illuminate correctly at this level and on one side, I sent the flash to a plate overhead and then directed that back down to the bug; the other flash I just aimed directly from a distance. Neither flash had to have power levels beyond 1/2 full. I kept aperture where I had it at 18mm-- estimated at f/7-9. No evidence of flaring or other problems at this level. This experiment I think proves to me that this lens really wasn't designed for the much higher powers, and it is probably best to stick under 2-3:1. It *may* end up a good candidate for outdoor testing in the Spring. I still did have it reverse mounted on the 115mm of macro tubes.
I must say that I am surprised at the detail I was able to acquire from the stack. Since the centipede is much larger than the ant, I increased the reverse lens zoom from the 18mm I had for the ant, to 55mm for this. At that level, I was able to fit about half of the centipede across the field. Attached it the result, about 30 frames stacked at 2.5:1. It was MUCH easier to get the flashes to illuminate correctly at this level and on one side, I sent the flash to a plate overhead and then directed that back down to the bug; the other flash I just aimed directly from a distance. Neither flash had to have power levels beyond 1/2 full. I kept aperture where I had it at 18mm-- estimated at f/7-9. No evidence of flaring or other problems at this level. This experiment I think proves to me that this lens really wasn't designed for the much higher powers, and it is probably best to stick under 2-3:1. It *may* end up a good candidate for outdoor testing in the Spring. I still did have it reverse mounted on the 115mm of macro tubes.