Celestron Handheld Digital Microscope Pro

[VAB2013]

Yes, from Amazon. Should arrive next week.

This is so great! I didn't even ask... very big smile on this girls' face Ray, thank you so much! Well folks, the Celestron Handheld Digital Microscope Pro will soon be in the hands of a photography expert! Can't ask for anything better than that!

[ray_parkhurst]

I got my Celestron USB scope yesterday, and tested it out a bit last night and today. I am not done with the evaluation but wanted to give some first impressions before going further:

- The scope plugged in and worked first time upon running the program. No issues with installation. I'm running Win7 Pro
- The minimum magnification is just a bit too low to frame a full Lincoln Cent. It's a shame the post on the stand is not a bit taller, as that would allow a full Cent to be framed
- The focus adjust knob is very stiff. I don't know why, as it doesn't need to be. I'm going to try to loosen it up.
- Because of the way the optics work, it operates in 2 ranges: Low mag from slightly smaller than a Cent to about 1/2 of a Cent; High mag starting at slightly smaller than the date and going down to a wide MM shot.
- The "dead zone" magnification range is an important one...it includes the "money shot" of the full date and MM. I think this can be improved with some modifications and I will try to do this.
- The scope claims "full 5MP sensor" but I don't believe it. I took shots in 5MP, 3MP, 2MP, and 1.3MP modes. I find the best resolution in the 3MP mode.
- The software gives no control over exposure, white balance, etc. It's very simple to use, but does not allow best performance to be adjusted. It told me there was a "new" driver and program, but it just pointed to the same one that came with the scope
- Lighting is VERY blue, so much so that it's impossible to do a simple white balance adjustment after shooting. This basically means the lights are not useable for imaging with true color. I was able to do some level of adjustment after the fact but it's not particularly accurate
- The software over-sharpens the image. This is somewhat expected due to the relatively low resolution, but it limits the ability to focus stack
- The limited resolution makes 3D rendering almost impossible (see example below)

Here is a an image at max magnification without any adjustments:



Same image with some level of WB compensation:



Here is a 6-image stack of the same view:



Here is the same stacked image, rendered in 3D. The high level of noise shows the resolution is not sufficient for 3D rendering:



Now, this is not a huge problem, as I was not expecting the scope to be able to do 3D rendering, but I was hoping it could!

Here is the lowest magnification available in the "high" range I described above:



My next steps are:

Remove the clear plastic shield limiting working distance. This should allow a wider range of magnification, hopefully allowing the "money shot" to be framed.
Remove the LED lights and replace with a diffuser
Possibly cut the end of the body to give more lighting flexibility

[TJ1952]

WoW!! That is sweetness!! Brilliant pics Ray!!

[VAB2013]

Thank you very much Ray! It is so cool that you are testing the Celestron Handheld Pro! Your images look great, there's certainly hope for us amateurs! I think your next steps will be even more exciting!

[ray_parkhurst]

I tried shooting with my usual Jansjo LED lights, and it became quickly obvious that the scope is heavily-optimized for white balance using the on-board LEDs. These LEDs have low R and very high B, so the R channel is cranked up and B is suppressed. When trying to use a Jansjo, which is a "warm" LED with lots of R, the R channel is driven to saturation. I must conclude it's not possible to white balance using the Jansjos. The best you can do is using the internal LEDs and adjust white balance manually with a gray reference, then use those settings to adjust levels on each image. That's what I did with the images above.

[ray_parkhurst]

One issue I'm having is that it's hard to focus the scope due to the flexibility of the mounting post, combined with the stiffness of the focusing block. I think this will improve if I can loosen the focus block, but for now it's sort of trial and error. Focus best you can, then let go of the knob, then re-focus a bit, and repeat until you get the shot in best focus.


Edited to add:

I found out why it was so tight...the focus knob was all the way CW, which was "locked". I turned it all the way CCW and now it is very reasonable. The post is still pretty flexible so I'll need to look into how to stiffen it.

[VAB2013]

I tried shooting with my usual Jansjo LED lights, and it became quickly obvious that the scope is heavily-optimized for white balance using the on-board LEDs. These LEDs have low R and very high B, so the R channel is cranked up and B is suppressed. When trying to use a Jansjo, which is a "warm" LED with lots of R, the R channel is driven to saturation. I must conclude it's not possible to white balance using the Jansjos. The best you can do is using the internal LEDs and adjust white balance manually with a gray reference, then use those settings to adjust levels on each image. That's what I did with the images above.

Ray, I'm going to need some help with this explanation... it just went "woof" over my head LOL! If we only knew half of what you know! I know you said you were going to try to remove the LED's and replace with a diffuser maybe after that is done I will understand this process better. So, there is no way to adjust software settings for Brightness, Contrast, Gamma, Hue, Saturation, Sharpness and Exposure? Not a White Balance (Red/Blue) setting adjustment?

[VAB2013]

One issue I'm having is that it's hard to focus the scope due to the flexibility of the mounting post, combined with the stiffness of the focusing block. I think this will improve if I can loosen the focus block, but for now it's sort of trial and error. Focus best you can, then let go of the knob, then re-focus a bit, and repeat until you get the shot in best focus.


Edited to add:

I found out why it was so tight...the focus knob was all the way CW, which was "locked". I turned it all the way CCW and now it is very reasonable. The post is still pretty flexible so I'll need to look into how to stiffen it.

Yay! That's a good thing, better than my idea of WD-40!

[jfines69]

Ray,
On the 3D image you were unable to balance the image out using the smoothness adjustment???

[ray_parkhurst]

Ray, I'm going to need some help with this explanation... it just went "woof" over my head LOL! If we only knew half of what you know! I know you said you were going to try to remove the LED's and replace with a diffuser maybe after that is done I will understand this process better. So, there is no way to adjust software settings for Brightness, Contrast, Gamma, Hue, Saturation, Sharpness and Exposure? Not a White Balance (Red/Blue) setting adjustment?

Correct, there is no adjustment for any parameters at all. I think that's probably the main limitation of this scope. They have optimized the white balance best they could for the particular LED's they selected. These LEDs are very blue, with very little red. The Jansjos are well-balanced, but with more red than blue, so when you use them with the scope, the built-in white balance makes the image bright red. Unfortunately, since the exposure is also optimized for the on-board LEDs, the red is over-exposed, so it's impossible to white balance after taking the image.

Bottom line I don't see any way to make this work with different lighting, so I don't see a reason to remove the on-board LEDs. Without white balance and exposure adjustments, that's the best you can do.