Is it a bird... a meteor... a seed?

Images taken in a controlled environment or with a posed subject. All subject types.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Is it a bird... a meteor... a seed?

Post by colohank »

Someone tracked this seed into the house after walking through our native buffalo grass (Bouteloua dactyloides) lawn. The seed, about 8mm long, has a shinier and more reflective surface than I might have guessed. I perched it on the tip of a very thin steel violin "E" string positioned axially behind the subject to shield the wire from view. Focus stack of 24 frames, aligned and merged using Affinity Photo software. Additional tweaks in LR6.

Nikon D810 w/ Nikkor 50mm f/1.8 lens @ f/11, mounted on a Nikon PB-6 bellows and Sunway Foto focusing rail. Constant LED key and fill lighting, with background color provided by the repurposed innards of a digital picture frame.

The complete removal of faint ghosts around some edges is apparently beyond my pay-grade.

Comments and suggestions welcome.
Attachments
buff2 (Custom).jpg

leonardturner
Posts: 713
Joined: Thu Mar 14, 2013 11:40 am
Location: Atlanta, GA, USA

Re: Is it a bird... a meteor... a seed?

Post by leonardturner »

An interesting image, nicely lit. Did you reverse your lens for these shots? If not, doing so and using a numerically smaller f-stop, like f5.6, might produce an even better result.

Leonard

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Re: Is it a bird... a meteor... a seed?

Post by colohank »

Thanks for the suggestion, Leonard. No, I didn't reverse the lens for this shot, but I have the necessary 52mm to F-mount adaptor. Will give it a try. I'm curious, though, as to why you think a wider aperture (f/5.6 vs. f/11) would be preferable. Do you believe diffraction is a problem at f/11?

leonardturner
Posts: 713
Joined: Thu Mar 14, 2013 11:40 am
Location: Atlanta, GA, USA

Re: Is it a bird... a meteor... a seed?

Post by leonardturner »

Yes, I do. Lenses are generally considered sharpest around 2 or 3 f-stops above wide open and diffraction loss becomes more significant as the stop becomes numerically higher. I shoot with my 2.8 macro at f-5.6 as a general default. That said, you may not see a much difference with this subject, but it's something to think about going forward when you are able to stack your images and so are not dependent on depth of field to capture enough of your subject.

Happy shooting!

Leonard

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Re: Is it a bird... a meteor... a seed?

Post by colohank »

As mentioned in my original post, the image of the seed was processed from a stack of 24 separate frames. Thus the evident ghosting along high contrast edges. Focus increments between frames, from near to far, were 5/32 mm each (1/8th revolution of the crank on my manual focus rail).

But yes, I should experiment more. I'll reverse my lens and try a wider aperture on my next subject.

I've attached a picture of the setup I used in my admittedly cluttered garage "studio."
Attachments
buff3.JPG

leonardturner
Posts: 713
Joined: Thu Mar 14, 2013 11:40 am
Location: Atlanta, GA, USA

Re: Is it a bird... a meteor... a seed?

Post by leonardturner »

Sorry, I wasn't clear in my last post. Yes, I understood that you did stack this image; my point was that since you are stacking anyway, you don't have the need to use a numerically high (small) f-stop as you might if you were doing a single image and thus dependent on depth of field to try to get more of your subject in relatively good apparent focus. You would simply shift the camera between shots in smaller increments to prevent banding. But at some point you will want a true macro lens; your 810 is capable of much more detail than is your current lens, reversed or not.

Leonard

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Re: Is it a bird... a meteor... a seed?

Post by colohank »

Thanks for your comments.

I own a Micro-Nikkor 105mm f/2.8 and use it for up to 1:1 work. On the bellows, it offers a greater working distance, but since it lacks an aperture ring, I have only three choices for controlling aperture, 1) use it wide open, 2) use it at its smallest aperture, or 3) use a wedge or tape to set the aperture at some intermediate but undetermined value by jamming the aperture lever on the mount. I choose not to do the latter, and the other two options don't yield satisfactory results. The 50mm f/1.8 D, while admittedly plasticy and modestly priced, is considered one of Nikon's sharpest lenses, and best of all, it has an aperture ring. I believe it delivers all the resolution the D810's sensor is capable of recording.

With a manual focus rail, I can reliably dial-in only relatively course focus increments -- down to 5/32 mm or so, equivalent to 1/8 turns of its little, non-indexed hand-crank. Since I'm new at this game, I'm not quite ready to shell out $600 for a basic StackShot and cable, though that may come in the future. At present, I'm content to do the best I can with what I have and to continue learning.

Whether or not the Affinity Photo software I use to align and merge images is up to the task is another matter. I'm sure it's not as capable as a good purpose-built stacking software, but for now, it's what I have to work with. Technique and fundamental understanding also play a role. Improvements in the former and acquisition of the latter should accrue with experience.

Lou Jost
Posts: 5942
Joined: Fri Sep 04, 2015 7:03 am
Location: Ecuador
Contact:

Re: Is it a bird... a meteor... a seed?

Post by Lou Jost »

I believe it delivers all the resolution the D810's sensor is capable of recording.
That may be true when the lens is used at the magnifications for which it was designed, but Leonard is completely right.

First off, that lens is made for reduction rather than magnification, so it the very least, it should be used in reverse when used for magnification. Then it will be doing what it was designed for.

Possibly more important, you have to think about diffraction when you are working at magnifications greater than about 0.5. On extension, the actual effective aperture you are using is the marked aperture times (m+1). If that number is greater than about 8 or 11, the image will be worse than what the sensor could resolve. If you are working at marked f/11 and the magnification is about 3x, you are working at an effective aperture of f/44, deeply within diffraction territory.

There are rings for setting the aperture on Nikon lenses, as long as the inside of the lens mount has the little black lever for the aperture.

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Re: Is it a bird... a meteor... a seed?

Post by colohank »

Thanks for your insights, Lou. I just ordered a 52mm aperture control ring for Nikon from B&H and look forward tio using it. I wasn't even aware that such a thing existed. It's a learning experience.

Lou Jost
Posts: 5942
Joined: Fri Sep 04, 2015 7:03 am
Location: Ecuador
Contact:

Re: Is it a bird... a meteor... a seed?

Post by Lou Jost »

I hope you will find that ring useful. Also, I recommend you order a reversing ring too, the Nikon BR-2 or BR-2A

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Re: Is it a bird... a meteor... a seed?

Post by colohank »

I already have a reversing ring.

Lou Jost
Posts: 5942
Joined: Fri Sep 04, 2015 7:03 am
Location: Ecuador
Contact:

Re: Is it a bird... a meteor... a seed?

Post by Lou Jost »

Excellent!

BugEZ
Posts: 850
Joined: Sat Mar 26, 2011 7:15 pm
Location: Loves Park Illinois

Re: Is it a bird... a meteor... a seed?

Post by BugEZ »

This is an interesting seed. I’m not a botanist but I suspect it is actually several seeds. It brings to mind zinnia seeds which have a spade shaped seed at the bottom that is connected to the dried remnant of the flower petal. When zinnia seeds are dropped the relatively heavy seed end tends to land first, pointy end down. The light end of the seed acts as a drag shoot to orient the falling seed. It may help scattered seeds find their way into the soil. I suspect something similar is at play here. If separated I suspect the tail would tend to orient the spade end down.

Thanks for sharing this!

Keith

tatler56
Posts: 80
Joined: Fri Sep 09, 2011 2:32 am
Location: South Beds, UK

Re: Is it a bird... a meteor... a seed?

Post by tatler56 »

I love those LED lights on small goosenecks! Where did you find them?

colohank
Posts: 113
Joined: Sat Jul 24, 2021 6:07 pm
Location: Fruita, Colorado, USA

Re: Is it a bird... a meteor... a seed?

Post by colohank »

I found them on Amazon. The brand name is/was Teckin -- of Chinese manufacture, no doubt, and reasonably priced. My most recent purchase of them was in March 2021, but a quick check of my order history suggests that that particular lamp is no longer available. If not available, Amazon lists a lot of similar products, so you might find something there that will meet your needs. I like them in particular because they offer three levels of illumination.

Post Reply Previous topicNext topic