My first stack with the new el-nikkor 50mm F/2.8

yeatzee · Post by **yeatzee** » Thu May 12, 2011 9:50 pm

Well despite not being finished thanks to a family member bumping the setup, I am incredibly pleased with the shot

It was only meant as a test but wow! This is the most ordinary fly I could possibly find yet up this close its fascinating. I have a couple striped flies to try next

60 images stacked, el nikkor reversed on extension tubes @ F/5.6, w/ homemade hood and my two flash setup for lighting.

Blue bottle fly by yeatzee (now 17, but still learning), on Flickr

jgknight · Post by **jgknight** » Fri May 13, 2011 5:01 am

This is stunning. Very beautiful.

DrLazer · Post by **DrLazer** » Fri May 13, 2011 6:35 am

It's a good start Tanner! I love the El-Nikkor lens, can't grumble at the quality for the price. Anything cheap that offers good results is good in my book.

A few things I would suggest.

- I think the light needs diffusing a little more, the highlight areas are a bit blown out, some pixels top out at 255. Either diffuse more, move the flash further away or turn the flash power down.
- Maybe crop the edges off a little, lots of open space.
- Personally I would like the see the stack extended a little further, if the antenna made it in it would have been nice. (I did the exact same thing on my last stack).
- I think 60 images is almost double what you would have needed, too many images don't hurt but if you work out the size of your slice beforehand, it saves you a bunch of time both whilst shooting and waiting for the stacking software to run.

Love the detail in the fly's body. I reckon that's as sharp as you can get with the El-Nik. Keep it up Tanner, can't wait to see your next one.

Keifer · Post by **Keifer** » Fri May 13, 2011 2:12 pm

Hi Yeatze

Great image really nice and sharp.

I have an EL Nikkor that i have never used. What step up / down rings did you use to attach it to you extension tubes?

Best Regards

Keifer

yeatzee · Post by **yeatzee** » Fri May 13, 2011 4:07 pm

DrLazer wrote:It's a good start Tanner! I love the El-Nikkor lens, can't grumble at the quality for the price. Anything cheap that offers good results is good in my book.

A few things I would suggest.

- I think the light needs diffusing a little more, the highlight areas are a bit blown out, some pixels top out at 255. Either diffuse more, move the flash further away or turn the flash power down.
- Maybe crop the edges off a little, lots of open space.
- Personally I would like the see the stack extended a little further, if the antenna made it in it would have been nice. (I did the exact same thing on my last stack).
- I think 60 images is almost double what you would have needed, too many images don't hurt but if you work out the size of your slice beforehand, it saves you a bunch of time both whilst shooting and waiting for the stacking software to run.

Love the detail in the fly's body. I reckon that's as sharp as you can get with the El-Nik. Keep it up Tanner, can't wait to see your next one.

like I said, a family member bumped the setup moving the insect cutting the stack short.
Nothing I can do about that :/
As for lighting, no matter what I did I could not fully keep out blown highlights even with extra diffusiom etc without negatively affecting the rest of the image. The individual frames ended up not having any actualy blown pixels but the stack did. I don't think its bad by any means though and the shadow detail I got between the head and body is pretty awesome!

I ditermined the increment steps by take two pictures and comparing them zoomed in until I got what looked like good overlap. The stacks flawless so I might be able to do it in less frames but im fine with expending the extra effort for a cleaner result.

For the record it is already cropped. Next time im going to try holding the insect sideways So I get more vertical headroom.

Sorry for errors, im on my phone

yeatzee · Post by **yeatzee** » Fri May 13, 2011 4:10 pm

Keifer wrote:Hi Yeatze

Great image really nice and sharp.

I have an EL Nikkor that i have never used. What step up / down rings did you use to attach it to you extension tubes?

Best Regards

Keifer

40.5 - 49mm / 49mm - kmount

ChrisLilley · Post by **ChrisLilley** » Sat May 14, 2011 5:20 am

yeatzee wrote:
DrLazer wrote: - I think 60 images is almost double what you would have needed, too many images don't hurt but if you work out the size of your slice beforehand, it saves you a bunch of time both whilst shooting and waiting for the stacking software to run.
I ditermined the increment steps by take two pictures and comparing them zoomed in until I got what looked like good overlap. The stacks flawless so I might be able to do it in less frames but im fine with expending the extra effort for a cleaner result.

Tanner, the way you determined the step size looks sound to me and the results show that it was a good one. DrLazer, what calculation made you conclude the step size was too small?

DrLazer · Post by **DrLazer** » Sat May 14, 2011 6:00 am

As for lighting, no matter what I did I could not fully keep out blown highlights even with extra diffusiom etc without negatively affecting the rest of the image. The individual frames ended up not having any actualy blown pixels but the stack did. I don't think its bad by any means though and the shadow detail I got between the head and body is pretty awesome!

Lighting is frustrating isn't it. I have been through about 50 different setups and I still don't think I have found one that works as well as I would like. I'm starting to realise that it's a case of lighting each stack differently. It depends on the subject size, focal length etc. The macro masters in my opinion are set apart by their ability to light anything beautifully. Have a glance through John Hallmen's or Nikola Rahme's stream - lots of pictures of their setups on there too. It's not bad at all Tanner, I'm just helping you improve for next time. If you say the individual frames don't have blown pixels but the stack does. .... my memory fails me but one of the stacking methods alters the contrast and the other one doesn't. Might be worth switching from PMAX to DMAP or vice versa .. maybe even retouching from one result to the other.

Tanner, the way you determined the step size looks sound to me and the results show that it was a good one. DrLazer, what calculation made you conclude the step size was too small?

If I followed that logic then I might aswell stack a large fly with 1000 frames. The results will still be tack sharp, but it hasn't proved the method was good. There are the equations required to calculate your DoF and recommended step size all over this forum. Ultimately I want to be stacking more living bugs in the field and the studio work gives me the required practice and knowledge of stacking. I don't really want to be taking 2 or 3 times as long stacking a bug as what is required .. I might miss the opportunity as it flys away or moves on. The result in this case would look identical with a smaller step size, so you might aswell save yourself the time in the studio too.

I roughly know the size of the Lucillia illustris and I have the El-Nik lens myself. Without resolving any equations, this bee is about 1/4 the size of the pictured subject, I stacked it at a ratio of 3:1 and used 40 frames in total. When I calculated my DoF for that stack I went with 80% overlap which is still more than required.

rjlittlefield · Post by **rjlittlefield** » Sat May 14, 2011 8:08 am

yeatzee wrote:
DrLazer wrote: - I think 60 images is almost double what you would have needed, too many images don't hurt but if you work out the size of your slice beforehand, it saves you a bunch of time both whilst shooting and waiting for the stacking software to run.
I ditermined the increment steps by take two pictures and comparing them zoomed in until I got what looked like good overlap.

The experimental method that Tanner used is very close to what I normally recommend. I recommend to actually process a test stack, as opposed to stopping with the eyeball estimate, but the key point is that ultimately the step size is determined by experiment and not by calculation.

The reason for that recommendation is that it's robust and it takes into account every factor that matters for the user's setup.

Calculating is great (I made a career doing it), but the standard formulas for DOF are based on assumptions that are often not true in practice and depend on things you might not even think to check. It turns out, for example, that at 1:1 using manufacturers' recommended macro lenses, there is a 2X difference in DOF between certain Nikon and Canon cameras that are set to the same f-number. That's because the Canon setting means nominal f-number, while the Nikon setting means effective f-number after taking magnification into account. Using the EL Nikkor reversed on extension tubes, Tanner's setup does happen to correspond pretty well with the most commonly used standard formula that TDF = 2*C*f_r*(m+1)/(m^2) [from Lefkowitz "Manual of Closeup Photography", page 258]. Then the only question is what should C be, and again that number can reasonably vary by 2X depending on intended use for the image. The standard numbers are based on acceptably sharp when viewed at normal viewing distance, which corresponds to somewhat blurred when peeping at actual pixels.

I don't want to harp on this, but it's a serious caution. Trial-and-error is generally reliable, calculations not so much.

If Tanner happened to save the original frames, then there's an easy test to tell for sure whether 30 frames would have been enough. Just reprocess the stack using every other frame, and see whether it degrades.

but one of the stacking methods alters the contrast and the other one doesn't. Might be worth switching from PMAX to DMAP or vice versa .. maybe even retouching from one result to the other.

In Zerene Stacker, it's PMax that does and DMap that doesn't. In CombineZP, Pyramoid Maximum Contrast does and most of the others don't. I'm not sure which software Tanner is using these days.

--Rik

ChrisLilley · Post by **ChrisLilley** » Sat May 14, 2011 9:22 am

DrLazer wrote:
Tanner, the way you determined the step size looks sound to me and the results show that it was a good one. DrLazer, what calculation made you conclude the step size was too small?
If I followed that logic then I might aswell stack a large fly with 1000 frames. The results will still be tack sharp, but it hasn't proved the method was good.

Well, "lets arbitrarily pick 1000 frames" wasn't the method Tanner used. Instead, he determined the stepsize by checking there was sufficient overlap - not too much, not too little.

DrLazer wrote: There are the equations required to calculate your DoF and recommended step size all over this forum.

They are yes, and its what I use myself. So I was expecting you to have already used them, or to be about to use them, but instead:

DrLazer wrote: I roughly know the size of the Lucillia illustris and I have the El-Nik lens myself. Without resolving any equations,

hmm. Have you calculated the step size for this setup, or haven't you? And if you have, how does it compare with what Tanner used?

ChrisR · Post by **ChrisR** » Sat May 14, 2011 10:15 am

Either diffuse more, move the flash further away or turn the flash power down.

Diffusing more will give more diffuson (

) and relatively less bright highlights
Moving the flash further AWAY could mean that the angle it makes at the subject is NARROWER, which would lead to a LESS diffuse light. That one depends where the diffuser is, and how big. Ie whether it stays with the subject or the flash.
Turning the flash down, means the exposure's longer, so you're back where you started.

Things are very pernickety. I can do portrait lighting to a point, but when the studio's measured in millimeters, it's hard!

DrLazer · Post by **DrLazer** » Sat May 14, 2011 10:22 am

Interesting reading rik. Checking a quick processed stack is generally how I've done it up to now. The equations were my starting point though and I think I ended up using less than what I calculated for whatever reason
. I'm only on mu4/3 sized sensor though so I get a bit extra out of each slice (only based on the equation). Anyway the point was that its good to learn how many frames you need as a minimum.

DrLazer · Post by **DrLazer** » Sat May 14, 2011 10:25 am

@chrisR rock hard! I struggle really badly with it. It's hard enough for portraiture.

DrLazer · Post by **DrLazer** » Sat May 14, 2011 10:32 am

@chrisLilley. No I haven't, but 60 sounds like a lot for a large fly. Would you expect to use 60 frames for as much Green bottle as what is in view? If you would I think I need to re check all my stacks. :S

Charles Krebs · Post by **Charles Krebs** » Sat May 14, 2011 10:42 am

You should not assume that in 100% of the cases you can modify the light quality to get good highlight (or shadow) detail throughout a subject like this. On many flies there are areas on the face (in this case around the eyes) that seem to be extremely reflective. If you expose to retain detail in these areas, the remainder of the shot will be underexposed. Sometimes it is necessary to shoot two exposures at each step and then, in PP, take the highlights from the darker version. For a small area as in this particular image you can go back and just shoot the offending section a stop or two darker. However when you do it this way (as opposed to running a full "darker" stack), you may need to do a little "resizing" when incorporating the sections since the stacking software will make slightly different "decisions" on sizing the various images.

Hard to say, but it does appear that in this particular image the light may be slightly "hotter" on the head of the fly, which would serve to make this issue more prominent.