Possible 10 Watt LED Light Source..

[billbillt]

I have not done this one yet, but it looks like another easy LED light source... It would be reminiscent of the old external lighting sources for microscopes... It would give plenty of adjustment as it is mounted in it's own housing...At 10 W it would be more than bright enough..

http://www.ebay.com/itm/201340103856?_t ... EBIDX%3AIT

Here is the power supply for it:

http://www.ebay.com/itm/151578998653?ss ... Track=true

I am not real sure about dissipation of the heat, as it was intended to be submerged with probably the surrounding water expected to draw away the heat.. Still, for less that $15 USD it would be cheap for such a bright source...

[zzffnn]

Bill,

I use these two LED headlamps:

http://www.amazon.com/gp/product/B00SWQ ... detailpage

http://www.amazon.com/gp/product/B00GFM ... detailpage

They fit under the stages of most microscopes, once you take off the straps and putty them there. Battery compartment is included. Just add battery. Very little DIY needed. They (especially the 1st light) are less than 10w but are still too bright for regular bight field. But they are perfect for oblique, darkfield or combination thereof.

I use those LED lights with a DIY filter combining the effects of oblique and darkfield (with adjustable background darkness and adjustable contrast).

Details of the DIY filter can be found here:
http://www.photomacrography.net/forum/v ... ht=#173390

Original filter invention was mentioned here:
http://www.photomacrography.net/forum/v ... hp?t=15142

I have tested the LED filter combo and they performed really well (tested using Klaus Kemp test diatoms).

Field aperture of the LEDs can be controlled using their zoom feature (while checking objective back lens through empty eye tube).

A frosted glass diffuser can be added on top of the LED for more even light.

And a gooseneck holder will hold those LED lights as overhead lights for stereo scopes:

http://www.amazon.com/gp/product/B00G3Z ... detailpage

All are portable.

[75RR]

Hi zzffnn,
thanks for the link to gradient jpg: http://www.photomacrography.net/forum/v ... ht=#173390
Do you have any images in which they are used?

On the two LED headlamps - I tried a similar one and found banding on all but the max setting, did you also have this problem?

[zzffnn]

Hi 75RR,

If you read my thread again, you will find that the 3rd post links to a poor photo of mine that was out of focus (sorry I have not got time to take better pictures, but based on visual observation, I can tell you that GUF [gradient universal filter] is very capable if you optimize it in your system). It will work in any magnification or NA, as long as your filter covers the entire aperture of the objective used (high NA is not easy and does need more tweaking of filter size, but doable).

The LED and GUF combo resolved striae of Frustulia rhomboides on my scopes (using water immersion 65x /NA1.1 objective - higher power oil objective should work even better).

For better sample photos from others, please clink on the original link provided in the 1st post of that thread.

Yes, those LEDs have banding that only shows up in camera. Max setting has no banding. My eyes cannot see banding though. Max setting is perfect when used with GUF, because GUF acts like aperture diaphragm and blocks out most light (so it is not too bright to eyes). And you can control brightness/contrast by sliding GUF left to right and up and down. Also, the 2nd LED light is weaker than the 1st. I mostly used the weaker LED for objective <=40x /NA 0.65 with GUF and the brighter LED at >= 40x / NA 0.65 (mostly with a water immersion 65x / NA 1.1 and GUF). But the weaker LED will still work for 65x /NA 1.1

[75RR]

Thanks zzffnn, will give your gradients a try.

[billbillt]

Hello Fan,
Thanks so much for the info and the links.... I think I have a similar headlight around here someplace... If I can't find it, one of these will do... How do you like the Digital Camera Adapter Mount that you have pictured?... I had thought about getting one...
http://www.ebay.com/itm/300834440185?_t ... EBIDX%3AIT

Also maybe one of these to try your method out..

http://www.ebay.com/itm/391075508191?_t ... EBIDX%3AIT

Do you think it could be used in a similar fashion as your ND filter?...
Thanks!
Billt

[zzffnn]

Bill,

You have sharp eyes and did some great digging work! In theory, both of the products that you linked should work.

My concern for the adapter you linked to is:

It is $20, as opposed to my branded adapter at $50. Does Orion charge $30 just to stamp its brand name? I hope they are of the same quality. Please let me know if it works for you, I am actually tempted to buy another (cheaper) one. I did like my Orion adapter.

I did read, from Amazon reviews, that some cheaper adapters do not provide a secure hold. That secure hold and accurate positioning is quite important for image quality and it takes some fiddling even with my mostly metal adapter. Good plastic frame should work the same though, in theory, but I would want all screws and all sliding rails to be metal (if you have to have metal parts, do ask that eBay seller, as it is not mentioned).

My concern for the gradient filter you linked to is:

Its gradient seems too abrupt (I could see bands), bases on the photo shown on that eBay page. Maybe ask the seller if that is a real photo of the gradient filter (if not, have him send you a real photo).

My very first gradient filter (received from the original inventor) had abrupt gradient and it did not provide even lighting at > = 400x. For the following filters that I made, I spent time on computer to make SMOOTH gradient (that worked better). Ideally, you want the entire gradient to nearly overlap with the aperture of your objective back lens - meaning the beginning of the gradient be slightly over one side of you objective back lens, and the end of the gradient be slightly over the other side of the objective (the entire aperture should be covered) and you should not see obvious gradient bands.

Edit: Bill, if you don't mind to wait for a week or so, I can send you some printed filter sheets for free. Please PM your address. I should be able to get to a printing shop (OfficeMax) this weekend, if my baby cooperates.

[billbillt]

Hi Fan,

I am sure your Orion camera mount is much better than the one I posted from Ebay... It even looks more rigid to me.... I just posted about the design... It looks like it will work... How about these filters?

http://www.ebay.com/itm/400493886883?_t ... EBIDX%3AIT

I am sending you a PM....

[zzffnn]

Bill,

How to place GUF and how to check it can be found in the last post (with photos) in this thread: http://www.photomacrography.net/forum/v ... 507#173507

From the post right above that last post, you can download my new template too. This template should work for most condensers. The first template posted has more width and length for trials.

I am actually not sure if my Orion adapter will work better than the one you posted. My eyes could not tell a difference based on posted photos of the adapters. I bought the Orion as there were more positive reviews on Amazon. I like it after using it. But I think it is a little overpriced for what it does (though it does it well).

The second filter that you posted still look uneven to my eyes. I could see a band that separates white and dark portions. Maybe it is the seller's photography light that made it look that way. On a good gradient filter, you should see no separating bands (it should be an even continuous gradient from light grey to dark grey to black).

[billbillt]

Hi Fan,
It is just to me, the Orion mount just looks more robust... Are your gradient filters printed with a desk jet printer?... that is the only kind I have...

[zzffnn]

Bill,

Any printer will work - just download my jpeg template and print directly. I just don't have transparent sheets at home with me.

So I will have to go to OfficeMax to print. I saw some clear projector sheets for sale, but those are a bit expensive (and I don't need much). Surprisingly, OfficeMax provides similar sheets for printing at much cheaper price. I don't know what material it is though - probably not the same as heat resistant projector sheets. Any printable clear sheet that is firm enough (won't collapse with its own weight) should work, I guess.

Edit:

The following two items should work, I will order some next time:

http://www.amazon.com/gp/aw/d/B00KW8852 ... 9HPW9N1D4R

http://www.amazon.com/gp/aw/d/B000XALNP ... 8H75AP4A2M

Best,
Fan

[gekko]

Just a reminder that transparencies are made specifically for either laser or inkjet printers (as far as I know they are not interchangeable: laser printer transparencies need to be able to take the heat, and inkjet ones need to be able to absorb the ink in order to avoid smears). At least that is my understanding.

[zzffnn]

^ Good catch! I was not aware of that.

[Crater Eddie]

Just a reminder that transparencies are made specifically for either laser or inkjet printers (as far as I know they are not interchangeable: laser printer transparencies need to be able to take the heat, and inkjet ones need to be able to absorb the ink in order to avoid smears). At least that is my understanding.

I can tell you that I tried some laser printer transparencies in an inkjet printer. It looked good for a while, but the ink quickly smeared and made quite a mess.
CE

[75RR]

I can tell you that I tried some laser printer transparencies in an inkjet printer. It looked good for a while, but the ink quickly smeared and made quite a mess.

Laser printer on Inkjet transparencies work better.
Either way best to print two of each and stick them together - ink on the inside.
This works well for stops as one obtains a more opaque result.
If design is complicated to reverse then backing with a clear sheet will do.
I use a mini drop of nail varnish on a clear part of the acetate at 12, 3, 6 and 9 O'clock.