A-PeeR Loc: Houston, Texas

I have been wanting to get an APC-S or M4/3's camera for my stacking rig. I believe smaller pixel size and higher pixel density will help resolve details better at higher magnifications. I really have my mind set on an Olympus O-MD E-M1 but couldn't justify the cost given the fact there isn't a reasonably priced electronic adapter to use my Canon lenses. Until the price drops, I decided to buy a used NEX-7. The plan is to use it primarily on the tabletop stacking rig or on a field stacking rig. It's light weight and portabality will allow me to carry the extra gear I needed for a proper field stacking rig, at least that's the plan. I took the camera out for a spin today and I'm quite impressed. I like the focus peaking feature. I was able to focus on subjects using the back LCD. I see advantages to this shooting method as it allows the photographer to quickly hone in on the subject and adjust the angle of the shot on the fly. It's going to take some practice but the technique intrigues me. Here are some photos from today, all handheld, most using the LCD and focus peaking - NEX-7, Sigma 105 Canon Mount w/Ommlite Electronic Adapter, 36mm Kenko Tube, Canon 430EX II with concave diffuser.

Robber Fly on Garden Fencing

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Robber Fly With Prey

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Green Lynx

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Wasps of Some Sorts

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Gotta Get a True Bug....

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Macronaut Loc: Redondo Beach,Ca.

Leave to you William to blaze new trails :wink: These look pretty darned good :thumbup:

Nikonian72 Loc: Chico CA

Image #2 is exceptional.

martinfisherphoto Loc: Lake Placid Florida

I'm actually of the opposite opinion, the larger the pixel the better the detail. That said, I hold your opinions in the highest regard and will wait to see how your experiment develops. Nothing ventured, nothing gained. In macro it all looks good on paper, but as we have found, when applied we sometimes come away with a whole new opinion or fact.

pfrancke Loc: cold Maine

Very nice - robber and wasps my favorites to look at. Your wasps looks so clean and crisp, I am assuming you used diffused light on them.

I love focus stacking on a rail so that you really don't have to worry much about finding that perfect focus. When I'm taking a non-rail shot, I guess I'm only comfortable using the view-finder. The LCDs always seem awful when out in daylight. And for my world when using live-view hooked to a tablet, the preview is nice, but the lag in the system is bothersome.

Some day (not in my lifetime) we will have multi-directional swivel rails remotely controlled, with a nice non-lagging live-view on a large monitor and then I can get the shots you guys do!!!

About the sensor, I always wonder if smaller (as a zoom multiplier) or larger full frame (that can be cropped) is better. For a rail, with your knowledge of microscope parts, getting past 5X should not be a concern, so I'd be on the lookout for most pixels on largest sensor.

A-PeeR Loc: Houston, Texas

Thanks Bill, I was happy with the results for a first go 'round...

A-PeeR Loc: Houston, Texas

Thanks Douglass, poor little long legged fly didn't stand a chance. I watched the robber on it's perch bolt and attack in a blink of an eye. Really fast how quickly it snagged the fly.

LoneRangeFinder Loc: Left field

Stunning results, no matter what gear you use.... I think that's the lesson here... although I tend to think like Martin.

I'd love to try shooting full frame macro... particularly on those critters that might be cropped in ASPC format.

There might be some advantage with smaller-sized critters.

I'll wait....

A-PeeR Loc: Houston, Texas

I think your opinion is dead on when it comes to “lower” magnification (up to 5:1) field shots Martin. Higher pixel density equals a smaller signal to noise ratio (noisier). Smaller pixels gather less light requiring greater illumination or higher ISO. Failure to do so means more noise. As you an I know noise grain erodes resolution and thus we have less detail. With the NEX field shots I could see more noise grain when compared to my typical FF sensor shots. I rarely use noise filters on the FF. All of these shots were run through NIK Dfine 2 to reduce background noise. NIK is a gentle noise filter but nonetheless detail is lost by running the photos through it.

Where I think the smaller pixel size / higher pixel density / smaller pixel size will be advantageous is in high magnification (10X-plus) tabletop stacks. I have run some tests with the FF at 20X and 40X and the edges on some fine details don’t seem sharp enough to me. My thinking was the pixels on the full frame are too large to accurately capture the details. It’s like transition edge areas are captured in a single pixel bucket and smeared out in the digital averaging.

I did some Googling and found Charles Krebs’ spreadsheet that calculates the finest detail an objective can resolve and the pixel density needed to capture this detail. At a bare minimum Charles suggests 2 pixels per smallest resolvable optical detail (ROD). My 22MP 5DIII puts ~2.5 pixels on the smallest ROD. The 24MP APC-S NEX 7 puts ~4.2 pixels on the smallest ROD. It remains to be seen if I can get enough illumination on the subject to cancel out the noise factor of the APC-S sensor. Given my experiences with the concave diffuser on my stacking rig I think the noise tradeoff is manageable. For you Nikon buffs, on paper the D810 appears to be a high magnification stackers dream - full frame, no AA, and ~3.5 pixels on the smallest ROD with the typical 20X .4 NA objective. The Olympus O-MD EM-1 trumps it theoretically - no AA filter and a whooping ~ 5 pixels on the smallest ROD but with a noisier, smaller sensor. Like all things in photography, always tradeoffs or as Douglass likes to say no free lunch.

As we both know theoretical numbers are good guidelines but not the end all be all. The proof will be in the final image, which I eagerly want to start but I am waiting on an IR remote to trigger the camera…

tinusbum Loc: east texas

nice shots william,i saw a robberfly down a dragonfly one day.it was great

A-PeeR Loc: Houston, Texas

Thank you Piet, yes I used my concave diffuser. I need to build one a bit smaller for this rig as it’s front heavy. Thinking of adding my own Fresnel, (think Better Beamer like the bird photographers use) inside the hardbox and employing a smaller flash head.

Push comes to shove I prefer the optical viewfinder (OVF) over the electronic (EVF). Colors are more true and my brain can tell I’m looking at a digitally rendered image. I haven't noticed any discernible lag. One thing I do like about the EVF is the captured image is displayed right after the shot so you get a good idea if the exposure is good and the focus is in the ballpark. Critical focus detail(s) need to be reviewed on the LCD. I too was concerned about the LCD being to dark. I found keeping the camera close to my body shielded the ambient light and viewing was good. Add too that, the peak focusing comes in bright yellow or bright red, it is easy to see where critical focus falls. I did find it’s not great at picking up areas with low contrast, for example the facets on fly's eye. From experience I knew where the hairs above the eye were. When the eye facets didn’t peak and the hairs did I was able to make adjustments (pull back the camera) and get the shot. With more practice I hope to get better at picking up the nuances of peak focusing.

I don’t think you need to wait for improvements in equipment to take good field shots. Your stacks show you have the equipment. You need to go out and practice. There is no substitute for time spent in the field shooting. Field shooting also has the added benefit of peace and tranquility, you, the camera, nature and not a care in the world. I recharge my mental batteries every time I go out and shoot.

As you push past 10X pixel density becomes more critical in resolving fine details.

pfrancke Loc: cold Maine

hey William, thank you. I've enjoyed very much reading the things you say in this thread. In my case, crystal clear response to inane rambling.

A-PeeR Loc: Houston, Texas

Thank you Allen. I thought about the old adage it's not the gear it's the photographer when I was using this camera. It's not so much the photographer but the experiences one has gone through to understand how to use the gear and how to shoot the subject..

There are advantages to a FF camera. Shooting larger subjects is one of those. I can name a half dozen other reasons I like a FF camera. The NEX 7 has advantages too and it's a lot of fun to shoot. That said it won't be replacing the 5D-III as my go to field camera. I do have high hopes it is going to pan out as my go to stacking rig camera.

A-PeeR Loc: Houston, Texas

Thanks Tom, it is a great experience to watch 'em hunt. This guy went after a Skipper too. Skipper was just a tad quicker, which surprised me. No wonder they're so skittish when we try to photograph them...

A-PeeR Loc: Houston, Texas

You welcome Piet. Glad you you got some benefit out of the thread. Inane, nah just sounds like you are a bit frustrated at what you can shoot and in the field. There's only one way to correct that, go out, shoot, shoot, shoot, and enjoy it......