Advice on a dark field camera

[Numanoid]

Hi all, new user here and a new hobbyist to the world of microscopy. I've got a cheap setup (amscope/Omax) but have been loving microbe hunting and taking pics and videos. I need advice on a camera setup that I can use for dark field videos. My omax 18mp just can't cut it due to its tiny pixel size. I've been told I should be looking for a pixel size above 3 microns and adjustable gain would be preferable. I'm open with my price range if it's got the features I'm looking for . Ideally it would be under $1000. Minimum of 1920x1080 @ 20ish fps so I can capture "nice" videos. Higher res/fps is a bonus.

I read an interesting post here about the Altair Hypercam 183 (used for astrophotography) and it's really piqued my interest. The pixel size is only 2.4 microns (still nearly double my Omax), but it seems to be designed for low light situations. 20MP and high frame rate overall.

Any information you can provide would be helpful. Links to products, explanation on what I should be looking for, etc.

Thanks!

[daruosha]

Hi,

With 1000 USD budget, I would recommend a DSLR camera. You'll have full control over exposure settings and much higher dynamic range. Something like Canon EOS 750D/800D.

[apochronaut]

A big problem with DF is the dynamic range of the camera. The brightly illuminated portions of the image, can tend to flare badly with some cameras and metering systems, because it is trying to average the metering. I don't have a great camera but have had good results by stopping down and lengthening the exposure time.
Doesn't work with fast critters.

One thing to watch out for, is the stability of the system. DSLRs are heavy and there is no real need for the mirror on a microscope. It's kind of a design holdover from the SLR. Buying new; there are few reasons not to investigate a mirrorless camera.

[daruosha]

One thing to watch out for, is the stability of the system. DSLRs are heavy and there is no real need for the mirror on a microscope. It's kind of a design holdover from the SLR. Buying new; there are few reasons not to investigate a mirrorless camera.

On second though I was going to come back and modify my post for a mirror-less camera recommendation. As apochronaut said, go for a mirror-less camera.

[Hobbyst46]

Hi all, new user here and a new hobbyist to the world of microscopy. I've got a cheap setup (amscope/Omax) but have been loving microbe hunting and taking pics and videos. I need advice on a camera setup that I can use for dark field videos. My omax 18mp just can't cut it due to its tiny pixel size. I've been told I should be looking for a pixel size above 3 microns and adjustable gain would be preferable. I'm open with my price range if it's got the features I'm looking for . Ideally it would be under $1000. Minimum of 1920x1080 @ 20ish fps so I can capture "nice" videos. Higher res/fps is a bonus.

I read an interesting post here about the Altair Hypercam 183 (used for astrophotography) and it's really piqued my interest. The pixel size is only 2.4 microns (still nearly double my Omax), but it seems to be designed for low light situations. 20MP and high frame rate overall.

Any information you can provide would be helpful. Links to products, explanation on what I should be looking for, etc.

Thanks!

The Altair camera really seems promising, to me. Unfortunately, it was never again mentioned on this forum, so there are no feedbacks and second opinions on it. If suggested for astronomy, it must be very sensitive. On the other hand, for DF, sensitivity is not the most important virtue.
If you go for a mirror-less camera, I would suggest to verify that it can be remotely controlled from a computer. Not all of them do. For example, of the 10 or so mirrorless Canon cameras (I do not endorse Canon in any sense), only the M50 and R models allow tethering.

[Numanoid]

The Altair camera really seems promising, to me. Unfortunately, it was never again mentioned on this forum, so there are no feedbacks and second opinions on it. If suggested for astronomy, it must be very sensitive. On the other hand, for DF, sensitivity is not the most important virtue.
If you go for a mirror-less camera, I would suggest to verify that it can be remotely controlled from a computer. Not all of them do. For example, of the 10 or so mirrorless Canon cameras (I do not endorse Canon in any sense), only the M50 and R models allow tethering.

I love the idea of a DSLR since it could be double purpose, but the bulkiness is definitely a turn off for me. I've found it very difficult to find microscopy use of the Altair cameras, but I do see that they market c mounts for microscopes for said hypercams. I stumbled on this yesterday as well: It's a Altair 294C 11.6MP with a 4.6 micron sensor posted from Altair Astro's youtube site. Now their microscope is several orders of magnitude better than mine, but I'm damn impressed with the videos. 35 FPS at max resolution as well.

Dark Field: https://www.youtube.com/watch?v=_g0yx69wm8Q

Phase Contrast: https://www.youtube.com/watch?v=fDMEPft7DA4

Bright Field: https://www.youtube.com/watch?v=QHDRWxBPtnE

I'm going to try to dig up more information on these hypercams. The 294C is running $800. For Perspective, my comparitivelt crappy Omax was nearly $500. It's still in the return window, too.

[Hobbyst46]

Why not search the keyword "Altair" on this forum as well as on the macrophotograpy forum.

[Numanoid]

Why not search the keyword "Altair" on this forum as well as on the macrophotograpy forum.

I did last night and it returned only the thread where it was first mentioned. Now this thread is also being returned in the results.

[Hobbyst46]

Why not search the keyword "Altair" on this forum as well as on the macrophotograpy forum.

I did last night and it returned only the thread where it was first mentioned. Now this thread is also being returned in the results.

The ALtair is fairly expensive, given that it is not a true "microscope brand" camera on the one hand, and lacks the functions of a DSLR/mirrorless on the other hand. The price might reflect the sensitivity, but again, sensitivity would matter for fluorescence, and much less for other illumination modes.
Microscopists have produced fantastic images with DSLR's.
If, in your microscope, the arm is fixed, and all focusing involves the stage alone (or some other part that is not the arm or head), the weight of the camera should not matter too much.
And if the camera is tethered to a PC/laptop, you barely touch it during sessions.

[MichaelG.]

That 294c does look very impressive:

https://www.altairastro.com/altair-hype ... d-51-p.asp

The only thing I can see that might limit its high-speed performance in microscopy is the ‘rolling shutter’
... I didn’t see it mentioned on that page, but the next model up has ‘rolling shutter’ so it seems a reasonable assumption.

That said: The Daphnia heart video is superb !!


MichaelG.

[Numanoid]

What is a rolling shutter? And since people are seeing this, what kind of "reduction" lens would I want for a 4/3" sensor? 1x to 1.5x?

I'm having a hard time getting that figure.

[MichaelG.]

What is a rolling shutter? And since people are seeing this, what kind of "reduction" lens would I want for a 4/3" sensor? 1x to 1.5x?

I'm having a hard time getting that figure.

I will post something shortly, about ‘rolling’ vs ‘global’ shutters.

Meanwhile ... 1x works fine for a 4/3 sensor.

MichaelG.

.
This gives a concise explanation: https://s1-dl.theimagingsource.com/api/ ... .en_US.pdf
... Check the pictures of the fan !!

Wikipedia has a good page too: https://en.wikipedia.org/wiki/Rolling_shutter

[Numanoid]

That's pretty cool! Weird fan for sure. I think I've answered all the questions except how to mount the thing. Since this is for a telescope it's got a t thread M42x0.75 and a nice picture shows that there is a CS adapter ring and then the c mount adapter 5mm spacer. https://cdn.shoplightspeed.com/shops/60 ... /image.jpg

Unfortunately I can't locate these items on Altair site or their US distributor.

I think the former is this thing:
https://www.highpointscientific.com/zwo ... FFEALw_wcB

And the latter item is this:
https://www.amazon.com/Pixco-Adapter-Ex ... op?ie=UTF8

Then I pop it on to a 1x tube and I think that's it. Camera mounts are amazingly confusing.

[MichaelG.]

Looks good to me

MichaelG.

[Numanoid]

Hey all, I got the camera (Altair 294C) on Friday and thought I'd post a first thoughts/initial review of it. The short version is the camera is leaps and bounds better than the Omax I was using and only 25% more expensive.

I'm still learning its capabilities and the different software, but initial impressions are that it's wonderful. Crisp images, 30+ frame rate in full resolution (in live mode) and the pixel size (4.6 micron) makes exposure much easier than the 1.25 micron in the Omax. The software that comes with it is a rebranded toupview software made specifically for astrophotography. This is good and bad for me. The gain slider goes from 1 to 128 instead of 1 to 5 which gives me greater gradient of gain and a higher limit of gain which is very helpful for dark field. I can also record videos with default values instead of having to click through 5 dialogs to record in the other version. I lose, however, the ability to calibrate and provide measurement, which really sucks.

So even with the gain up and the large pixel size, dark field is not quite good enough at full resolution. That changes a lot when I use pixel binning, which this camera supports. On 2x2 binning I still get high resolution video with a ton of light capture. The resolution drop due to binning is just a trade off I need to make in order to capture more light. Dark field is a breeze with this and I can play with exposure time and gain to get the subject just right. Even less transparent subjects (like those dim wispy tentacled creatures) are easy to see and photograph when using binning. I haven't yet found a really good dark field subject (something that's really bright) that I can test non-binning capture on.

One thing that confounded me for a while was that I wasn't getting the advertised frame rate at capture in full resolution (35FPS) and it took me a while to figure out that it was because I was capturing in MP4 which requires processing during capture. This was never an issue with the Omax since even at quarter resolution I was only getting 15-18 fps due to the camera. I still need to play with the sweet spot on MP4 capture, or I can capture AVI at full res/fps and get about 500 meg/second file captures. Maybe an external temp drive for capture and then produce it into MP4 using handbrake or whatever editing suite.

Some final notes: I purchased from the UK site since the US distributor had the 294C as special order with a month lead time. The UK store was awesome and offered to send me both adapters needed for microscope for free. I had already placed the order and bought the 2 items in my previous post. Both of those items were the correct ones, but the first one (CS Adapter) was included in the box of the camera. To be clear, you only need the 5mm spacer (CS to C). The price in the UK store is cheaper than domestic even including shipping (DHL Express 3 day) and I highly recommend them.

I'm using a 1x relay lens and I don't like it. I see the circle of my tube and a lot of the capture is dark space. I'm on a quest to find a 1.2x relay and based on my reading here and elsewhere, it may be akin to finding the Ark of the Covenant. I'll be posting in the other section later today looking for suggestions.

If you made it this far in this rambling post, feel free to ask any questions or insight. I'll be sure to post some video/photo samples soon!

[Hobbyst46]

Congratulations. Waiting to see still images.
Please show the setup of the camera on the microscope. Do you think it can be used in series with an eyepiece ? not a special photo (or projective) but an ordinary eyepiece ? do they have a 0.5X lens to catch a larger field of view ? thnaks in advance.

[Numanoid]

Congratulations. Waiting to see still images.
Please show the setup of the camera on the microscope. Do you think it can be used in series with an eyepiece ? not a special photo (or projective) but an ordinary eyepiece ? do they have a 0.5X lens to catch a larger field of view ? thnaks in advance.

I'll preface everything here with my knowledge here is extremely limited and I found trying to understand mounts to be, by far, the hardest piece of this puzzle.

I'd say it all depends on the adapters available out there. It comes ready to use with a CS mount so if you can get that mounted to an adapter that can mate with an eyepiece, I think you'd be fine. Likewise with a C mount. Technically it comes native with an M42x0.75 mount so if you could source an adapter with that you could skip the others. I haven't seen any lens accessories for this camera from Altair, but if you had the adapter to mate to an eyepiece, you could potentially use a .05 reduction lens, but then you're back to using a projective lens.

If you head back to this thread viewtopic.php?f=9&t=7516&p=66342&hilit=altair#p66342 you can see how he mounted his camera directly to his base. I'm going into the trinocular port where the eyepiece would sit. I'd love to remove that piece but it's not a screw in mount, rather using 2 allen screws to hold it in place. I have no idea if this is a standard mount or Amscope specific. That's my next mission.

I'll get some pics out tonight.

[MichaelG.]

Technically it comes native with an M42x0.75 mount so if you could source an adapter with that you could skip the others.

At the risk of stating the obvious ...
May I just remind folks that M42x0.75 is the standard T-mount thread

MichaelG.

[Numanoid]

Technically it comes native with an M42x0.75 mount so if you could source an adapter with that you could skip the others.

At the risk of stating the obvious ...
May I just remind folks that M42x0.75 is the standard T-mount thread

MichaelG.

You wouldn't believe how many hours it took me to figure that out...

[Numanoid]

I got to play around a bit tonight and I have a video to post. Dark field photos and videos are a heck of a lot more complicated than bright field. I had a lot of fine tuning to get the exposure to a point where i could record. I have a feeling it's going to take many hours to really get the hang of this. Here's a vid I took after 30 minutes of playing with settings.

https://www.youtube.com/watch?v=YRlXZA3x56U

[MichaelG.]

That’s a great start ... Keep ‘em coming

MichaelG.

[Numanoid]

Congratulations. Waiting to see still images.
Please show the setup of the camera on the microscope. Do you think it can be used in series with an eyepiece ? not a special photo (or projective) but an ordinary eyepiece ? do they have a 0.5X lens to catch a larger field of view ? thnaks in advance.

Here's a pic of the camera on the scope. Right now it's camera -> 1x relay -> trinocular tube -> Scope.

Soon it will be Camera -> different 1x relay -> Scope.

https://imgur.com/a/DhGan63