Search found 160 matches

by c-krebs
Tue Aug 02, 2016 8:12 pm
Forum: Beginner's corner
Topic: Opinions on these objectives please?
Replies: 7
Views: 2172

Re: Opinions on these objectives please?

I`d eventually like to rig up something similar to Charles`s setup where he has the copy stand and bellows unit for his DSLR mounted above his scope, would these objectives suffice for now or what others would I need please?. Do all scope objectives have the same thread size? Any other info on thes...
by c-krebs
Tue Aug 02, 2016 12:32 am
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

gekko,

Very good point. Since kit1980 is using a tethered camera it should be possible to focus via a magnified image on the screen directly from the camera sensor.
by c-krebs
Mon Aug 01, 2016 10:40 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

This thread has wandered back and forth a bit but I find it interesting and I think the subject and discussion could be of use to many. I've looked through it from the beginning and here are some observations and thoughts. I hope they are deemed pertinent to the subject. We're trying to compare two ...
by c-krebs
Sat Jul 30, 2016 11:22 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

I would really like to see a flat, highly detailed subject that fills the entire frame. The two shots we have seen provide some valuable information but are really not suitable for judging the imaging characteristics. Here's what we see in the corner and center of the scale shot at 200% of the jpgs ...
by c-krebs
Sat Jul 30, 2016 12:28 am
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

Fan, All I wanted to do was indicate that all "CF" eyepieces (unlike the objectives) were clearly marked with a "CF". As with most major manufacturers they had a variety of powers, field numbers, and such... but all had the prefix "CF". Here are a half dozen different versions on Ebay right now: 162...
by c-krebs
Fri Jul 29, 2016 9:23 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

I could try to remove 0.5x lens, but it's a part of the adapter. Also there are some lenses in the bottom of the head and in the top of neck. No, don't try that. With the sensor size of that camera (and a great many "eyepiece" and scientific cameras) a 0.5X is necessary to "fit" the image properly ...
by c-krebs
Fri Jul 29, 2016 9:07 pm
Forum: Illumination Techniques
Topic: Plasmonics Enable Optical Microscopes to Perform Like Electron Microscopes
Replies: 6
Views: 2454

Re: Plasmonics Enable Optical Microscopes to Perform Like Electron Microscopes

Yes, very interesting indeed. About a year ago, I read an article( I will try to find it) about a group of researchers in, maybe Taiwan? : can't exactly remember where, that were using a grid of nano particles that acted collectively like a lens; basically a thin layer layed over the object to incre...
by c-krebs
Fri Jul 29, 2016 8:41 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

Initially... 1. A compatible objective should have 160/- or 160/0.17 markings, anything with the infinity symbol is not compatible with the OMAX. If the Omax is an infinity correct microscope then any objective marked "160/- or 160/0.17 " is not compatible. I don't believe this is the case. Kit1980....
by c-krebs
Thu Jul 28, 2016 9:34 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

A better comparison can be made in brightfield - perhaps with a Diatom Test Form as the subject or even a stage micrometer. I do agree. I would like to see some brightfield comparisons of a flat static subject in a permanent mount. There really are too many variables in what appears to be a rather ...
by c-krebs
Thu Jul 28, 2016 10:39 am
Forum: Pictures and Videos
Topic: Conochilus unicornis Rousselet
Replies: 11
Views: 2363

Re: Conochilus unicornis Rousselet

Thanks for the kind remarks. Charles! Are those eggs I see? Yes there were quite a few with eggs! What objective NA did you use for that oblique photo? If you increase the NA (at cost of losing focus depth), do you think unwanted shadows will be lessened? The objective used for the first oblique sho...
by c-krebs
Thu Jul 28, 2016 10:16 am
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

Second image is clearly better. (Hope that's the new objective ;) )
by c-krebs
Tue Jul 26, 2016 10:08 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

I am getting the impression that I have missed something in this thread: that the thread is about using objectives as photographic lenses.... ... Since the Omax microscope, presumably has either Korean or Chinese eyepieces, then, is the suggestion that using a Nikon CF objective would work perfectl...
by c-krebs
Mon Jul 25, 2016 9:19 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

Unless a person stares at edges of a single frame of a perfectly flat subject, (s)he won't notice field flatness issues with focus stacking and direct projection (objective directly to sensor). Absolutely... as long as it is solely a field flatness issue. I've used objectives that required some foc...
by c-krebs
Mon Jul 25, 2016 6:59 pm
Forum: Beginner's corner
Topic: Adapting Canon EOS to BH2 Trinocular.
Replies: 17
Views: 4473

Re: Adapting Canon EOS to BH2 Trinocular.

The top of the Olympus trinocular tube (on the BH-2 TR30 head) has a circular dovetail. While the "through hole" is the same diameter as the eyepiece tubes, the inner inner diameter of the dovetail section that juts up (about 10-15mm or so...guessing, didn't actually measure it) will not allow a "vi...
by c-krebs
Mon Jul 25, 2016 7:24 am
Forum: Miscellaneous
Topic: New lab for three big scopes
Replies: 16
Views: 2766

Re: New lab for three big scopes

Electrical outlets, more electrical outlets.... and then add a few more! ;) ;) Or a nice big power strip or two at the back of your counter a little higher than the counter height. (Not the typical "floor level" outlets like in the boring part of the house). My current space is a converted darkroom....
by c-krebs
Mon Jul 25, 2016 7:04 am
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

The fact that Nikon CF objectives are supposed to be chromatic aberration free and therfore not in need of compensation is pretty irrelevant because, first of all, they are not chromatic aberration free, otherwise they wouldn't be called achromats and secondly,the eyepieces for them are still uniqu...
by c-krebs
Sun Jul 24, 2016 11:52 pm
Forum: Pictures and Videos
Topic: Conochilus unicornis Rousselet
Replies: 11
Views: 2363

Conochilus unicornis Rousselet

There are a few subjects that just seem to make you smile and become favorites to watch. Volvox, Lacrymaria, tardigrades (water bears) come quickly to mind. Another for me is the colonial rotifer Conochilus unicornis. Here is a link to a video, and five images. The video is helpful to get an idea of...
by c-krebs
Sat Jul 23, 2016 10:32 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

Keep in mind I can't give you any definitive answers... never used your current optics, and I have only used one of the ones you have listed. #2) is out. Not "CF" and not 45mm parfocal. #3) I have, and have used. This the best "achromat" version of the Nikon CF 160mm finites. As I mentioned earlier ...
by c-krebs
Sat Jul 23, 2016 9:41 pm
Forum: Identification help
Topic: Mean Critter with Spikes
Replies: 7
Views: 1458

Re: Mean Critter with Spikes

Fascinating! Certainly looks like a rotifer, but I've not seen one with all those spines on the back of the lorica (that does not say much since there are 2200 species of described rotifers, the majority of which I have not seen ;) ) Nice find and pictures. I would think it is not that commonly seen.
by c-krebs
Sat Jul 23, 2016 8:17 pm
Forum: Microscopes and optics
Topic: Better objectives for a Chinese microscope
Replies: 72
Views: 11714

Re: Better objectives for a Chinese microscope

My first, second , and third choice for your situation is the same ;) .... Nikon CF objectives. They are excellent and can be found in (very good) Plan Achromat types as well as Plan Apo types (not cheap!). These are finite type, 160mm tube length, and 45mm parfocal (DIN). They do not require chroma...
by c-krebs
Fri Jul 22, 2016 12:53 am
Forum: Pictures and Videos
Topic: Swift phase 'scope first pics - needs work....
Replies: 17
Views: 1675

Re: Swift phase 'scope first pics - needs work....

John, Until you get a "proper" phase telescope try this simple method... works pretty good... Pull one eyepiece out (or use a spare eyepiece) and carefully hold it up, top to top (eye-lens to eye-lens) to the other eyepiece that is still inserted. Look into the back of the eyepiece you are holding a...
by c-krebs
Fri Jul 22, 2016 12:33 am
Forum: Pictures and Videos
Topic: Quick comparison - 2mp ToupCam vs 16mp Canon DSLR
Replies: 19
Views: 1745

Re: Quick comparison - 2mp ToupCam vs 16mp Canon DSLR

John, You made a good camera choice. I too think the Canon looks a bit better, although frankly in this comparison I would not expect to see much difference at all. That is because a 60X objective is not very demanding as far as sensor resolution is concerned. And this is especially so when you magn...
by c-krebs
Thu Jul 21, 2016 5:48 pm
Forum: Pictures and Videos
Topic: Plume de pigeon
Replies: 5
Views: 557

Re: Plume de pigeon

This is really a beautiful shot! Excellent!
by c-krebs
Thu Jul 21, 2016 5:41 pm
Forum: Beginner's corner
Topic: Dealing with evaporation
Replies: 7
Views: 1370

Re: Dealing with evaporation

(Note: I see Fan and vasselle have responded as I typed my reply... so I'm sorry for any duplication of thoughts. I suppose it doesn't hurt to hear it several different ways) An ideal wet mount will have a very thin layer of water just "deep" enough to avoid crushing your subjects. Now for the ones...
by c-krebs
Thu Jul 21, 2016 3:58 am
Forum: Pictures and Videos
Topic: Post Processing Play Time
Replies: 25
Views: 1478

Re: Post Processing Play Time

Kurt, I took the last two images you posted and did (in Photoshop) what I suggested just earlier. Here is an animated GIF to show how much cleaner the background can look if you use just a single source image (via retouching in Zerene). I don't even know if the last "single" image you posted would h...
by c-krebs
Thu Jul 21, 2016 3:30 am
Forum: Pictures and Videos
Topic: Post Processing Play Time
Replies: 25
Views: 1478

Re: Post Processing Play Time

Kurt, One thing you will find in some stacks like these is that the background can get really junky looking because you are picking up new debris from all levels and combining it all in your final image. Try taking the "finished" image back into retouching and select a single source image with the m...
by c-krebs
Thu Jul 21, 2016 1:53 am
Forum: Microscopes and optics
Topic: A question about microscope "alignment"
Replies: 11
Views: 1801

Re: A question about microscope "alignment"

If you are working on a compound microscope (not a stereo scope) with a 10X or higher objective you should be able to turn off (or set to "0") the adjustments for x/y position (alignment) and magnification. Then, any dust spots you have will not become "trails" but will be simple spots as would be t...
by c-krebs
Tue Jul 19, 2016 7:43 pm
Forum: Camera systems and imaging
Topic: DSLR Camera
Replies: 19
Views: 3528

Re: DSLR Camera

Rodney, What microscope do you have? What eyepieces? In particular, do you feel that the eyepiece tubes are substantial enough to hold the weight of the camera without stressing them too much? I`m at page 43 of the 323 page manual ;) ;) Not a bad idea (especially if you have never used a DSLR before...
by c-krebs
Tue Jul 19, 2016 7:28 pm
Forum: Pictures and Videos
Topic: DIY Rotating Video Glide Stages
Replies: 9
Views: 1347

Re: DIY Video Rotating Glide Stages

Tom,
Great! Thanks for posing this. Well thought out and executed.
It is surprising how few similar pieces are available "commercially" (with the exception of some very expensive large ones), I know...I've looked in the past. My mind is now percolating with ideas for my strereo stand.