50mm El_Nikkor vs 40mm Apo-Componon

A forum to ask questions, post setups, and generally discuss anything having to do with photomacrography and photomicroscopy.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

Joseph S. Wisniewski
Posts: 128
Joined: Fri Aug 15, 2008 1:53 pm
Location: Detroit, Michigan

Post by Joseph S. Wisniewski »

NikonUser wrote:My camera (D2Xs) will not fit onto the Nikon PB-6 bellows, the base of the camera is too deep. I have to mount an extension tube, a PN11 (52.5mm), between the bellows and the camera. I also have a complex lens mount at the other end of the bellows. Thus with the PN11 + bellows at full extension + lens mount (+ reversed for El Nikkor) I have a total extension of 325mm from the camera/lens mount. Can add another 50mm from the camera/lens mount to the sensor.
Hi NU.

That's almost the opposite of what I do. I thought being able to cover a larger range at a smaller magnification was more useful photographically, i.e. if you can get the extension range down to 133-275mm from the sensor (not counting the distance to the lens's rear node). So your shorter lenses all give you about a 3:1 range to play with:

the 63mm Luminar goes from 1x to 3.3x, a really nice range

another favorite, the 25mm Photar: an elegant 4x to 10x

I figure it's also perfect for 160mm or 210mm tube microscope objectives, basically 200 +/- 75mm.

To get to this point, I rummaged my junk drawer for the thinnest ring that would couple a D2X or D3 to a PB-4 and found the 14mm thick Nikon E2 ring. The RMS lenses mount with a custom made conical 30mm cone T mount to RMS adapter, the T mount itself adds 9mm. Reversed enlarger lenses end up a little closer, basically 120-262mm.

Of course, neither the enlarger lenses nor a few of the Luminars really hits their stride at such short extensions, and I often add another 100-200mm for those...

Just a little bit different way of looking at things.

ChrisLilley
Posts: 674
Joined: Sat May 01, 2010 6:12 am
Location: Nice, France (I'm British)

Post by ChrisLilley »

So (after re-reading this thread a couple of times) the limiting factor as a taking lens for photomacrography is diffraction due to effective aperture, which is more important than the measured MTFs at assorted magnifications?

In that case, for a 50mm lens used at f/5.6 (such as an el-nikkor 50/2.8 stopped down to f/5.6, or one of the fixed-aperture apo-componon-hm 50/5.6 mentioned by Klaus, a magnification of 3x would give an effective aperture of 5.6 * (1+3) = f/22 and thus slightly soft but acceptably good results, while higher magnifications would simply result in increasing amounts of diffusion and lower quality results?

DaveW
Posts: 1702
Joined: Fri Aug 04, 2006 4:29 am
Location: Nottingham, UK

Post by DaveW »

Nikon User.

Nikon say an extension tube should be used between their bellows and modern cameras if only so modern digital cameras with the hand-grip clear the rear standard. However they also claim that the "A" version of the small extension tube and reversing ring should be used with cameras having electronic contacts to protect them from the possibility of shorting. However many claim they use the old type rings without any trouble

What is not clear is why their longer extension tubes did not need an "A" type modification.

This subject was touched on here:-

http://www.photomacrography.net/forum/v ... 0a95c81c8d

Also:-

http://support.nikonusa.com/app/answers ... _id/116678

DaveW

rjlittlefield
Site Admin
Posts: 23561
Joined: Tue Aug 01, 2006 8:34 am
Location: Richland, Washington State, USA
Contact:

Post by rjlittlefield »

ChrisLilley wrote:So (after re-reading this thread a couple of times) the limiting factor as a taking lens for photomacrography is diffraction due to effective aperture, which is more important than the measured MTFs at assorted magnifications?

In that case, for a 50mm lens used at f/5.6 (such as an el-nikkor 50/2.8 stopped down to f/5.6, or one of the fixed-aperture apo-componon-hm 50/5.6 mentioned by Klaus, a magnification of 3x would give an effective aperture of 5.6 * (1+3) = f/22 and thus slightly soft but acceptably good results, while higher magnifications would simply result in increasing amounts of [diffraction] and lower quality results?
Generally correct. At a fixed aperture setting, increasing the magnification does get you a little more resolution on subject, but at the cost of a greatly reduced field size so that the final image ends up looking more blurred. I assume this is what you mean by "lower quality results".

This is the reason we use microscope objectives at higher magnifications. At 10X, it takes an objective with NA 0.25 to run at effective f/20 (=magnification/(2*NA)).

MTF figures would more be useful if they were reported for sufficiently high frequencies. Suppose I'm interested in pixel-level detail on my Canon T1i, at 3X. That sensor is 4752 pixels in 22.3 mm wide, 213 pixels per mm. If we assume four pixels per cycle, then I'm interested in 53 cycles per mm at the sensor. But at 3X, that's 159 cycles per mm at the subject. If the MTF charts included 80 and 160 cycles mm instead of stopping at 40, they would be very useful. But since they commonly stop at 40, there's a lot left to the imagination.

--Rik

DrLazer
Posts: 293
Joined: Wed Feb 16, 2011 4:45 am

Post by DrLazer »

Sorry to dig up an old thread.

Did we ever mange to get a comparison of the El-Nikkor and the Apo Componon at 100% pixels?

I just missed out on an auction for an Apo Componon which sold for £255 ($400). Is the Apo componon worth this much more than an El-Nikkor? I would LOVE to see a direct comparison between the two with images posted at 100% pixels, same subject, same lighting and as close of a matching exposure as possible.

I know John has posted some incredible images taken with the Apo Componon and this is mainly what attracted me to it. I do often wonder what kind of results he would have achieved with the El-Nik in the same situations.

ChrisR
Site Admin
Posts: 8668
Joined: Sat Mar 14, 2009 3:58 am
Location: Near London, UK

Post by ChrisR »

Still not great at 1:1, better at 2-3x, and diffraction squashes them both near 4x.
It's diminishing returns. You maybe have a DSLR and stuff worth say $1000 and you can make say 300mm prints showing no aberrations. If you'd paid $3000 perhaps you could go to 400mm.
Is that worth it?

I can do you a picture which shows a difference, and then two where there's no difference because of other factors getting in the way, like a touch of vibration, or flare, or suboptimal somethingorother. Then if spend all that money I have so much more stress in the trying, and so much disappointment after self-criticism

Do I listen to myself?
Moi? :oops:

DrLazer
Posts: 293
Joined: Wed Feb 16, 2011 4:45 am

Post by DrLazer »

Chris if you can post anything at 100% comparing them both I'd be very appreciative. I know what your saying about the prints. I'm talking 30" plus potentially. I also like viewing them digitally at full res.

I want to load up an image on my 50" TV at full res and think "boom! look at that" it's a personal thing really. Sometimes with the El-Nik the images look great, but then when I view them at 100% I feel like my eyes need a wash :(

naturephoto1
Posts: 509
Joined: Sun Nov 13, 2011 5:37 pm
Location: Breinigsville, PA
Contact:

Post by naturephoto1 »

DrLazer wrote:Chris if you can post anything at 100% comparing them both I'd be very appreciative. I know what your saying about the prints. I'm talking 30" plus potentially. I also like viewing them digitally at full res.

I want to load up an image on my 50" TV at full res and think "boom! look at that" it's a personal thing really. Sometimes with the El-Nik the images look great, but then when I view them at 100% I feel like my eyes need a wash :(
Hi Chris,

A few things to consider about print size. The first thing is that even with film (and high resolution digital scans) or digital output from the usual focal length lenses for ff 35mm 30" is still quite large, though in some instances perhaps you can print to 40" with still an acceptably sharp image. When you get into such high magnification though, don't forget how narrow the depth of field is in the image. I am not sure how much depth of field that you will maintain from stacking images never having done this at this point and and never having printed or seen digitally printed photo stacks.

Additionally the sharpest digital prints that I have from my work or have seen from any work are those that have been printed/output as metal prints printed to and fused to and into aluminum (a sublimation process) on the glossy surface. These images are just stunning. They are sharper than Fuji Crystal Archive photo paper. They need no glass in front of the image to protect them, can be dusted, are not subject to finger prints, can be washed with water, soap and water, and Windex. As a result they even sharper than Fuji Crystal Archive digital prints off of a Chromira Digital printer placed behind Museum Glass. The color of the metal prints also tends to be more saturated, sharper, better contrast, deeper blacks, more 3D affect with as Bill my printer likes to say they have more "Wow" factor. If you do have prints done this way, just be careful because the prints can be cut, dinged, dented and crumpled. My printer offers these prints with an optional 1/8" plastic mount behind the aluminum prints (something to consider and to look for for such printing method) which adds strength, rigidity, and much less flex than the aluminum prints alone that may be about 3 coke cans thick (.04" thick). Also, these are expensive prints and to the best of my knowledge the largest single blanks for these prints is 40" X 50".

Rich

ChrisR
Site Admin
Posts: 8668
Joined: Sat Mar 14, 2009 3:58 am
Location: Near London, UK

Post by ChrisR »

Hi Chris
Which Chris was that??

The figures I quoted for "print size" were of course illustrative, not actual...
I've never seen a picture on a 50" TV screen that was more than a couple of megapixels worth. At that, you wouldn't expect to see differences between lenses which could objectively be described as "good".
Again, what "acceptably sharp" on a screen like that means is a bit subjective?
(I've looked at lots of 50" screens in the shops, sometimes asking which is the best. The shop guys usually point to something with burned out highlights and silly colours and smothered in artefacts!)

I suppose you wouldn't use the EL-nik at 1:1 or 4:1 because it wouldn't be very good. It probably comes up best then somewhere around 3x. They vary. I have three of the things (but can only put my hand on one at the moment) - I once compared them and found small differences. I don't use any of them any more!
OK I can have a go , though knowing it could beaten by a bunch of others. There isn't an APO 50mm Schneider. It's much quicker to do stacks for comparison with the same FL to save fiddling...
Somewhere I have a planar 50mm f2 which might be OK, but I haven't seen it for a year or so. :(
Up at 4x, I wouldn't even try, a Nikon APO NA 0.2 objective beats, um, anything from Canon, Nikon, Schneider, Rodenstock or Olympus that I've put light through, between 35 and 75mm. But then we expected that ;)
It doesn't cover 24 x 36 though.
I have a Minolta 25mm f/2.5 lurking in a far off land, which might give it a run for its money. Oh and there's a 30mm f/2.8..!...
I still have a number to play around with. The overriding thing I've found though is that all the "good" ones are close, and comparisons are unreliable unless for the same type of shot. Try for yourself a stack done with the effective aperture too small - I bet you don't see much change on that 50" screen!
I am not sure how much depth of field that you will maintain from stacking images
Well, this is the whole point of stacking. You make sure that the DOF from one image overlaps with the next, so you can have as much as you care to cover, essentially.
If you use a higher resolving ( higher NA or higher F number) lens then your DOF is less and you need more images, slicing the subject depth more thinly.

Post Reply Previous topicNext topic