Search found 243 matches

by desertrat
Thu Mar 21, 2019 10:22 pm
Forum: Off Topic
Topic: Magnifying Glass
Replies: 6
Views: 3182

Re: Magnifying Glass

Years ago I bought a 5 piece plastic bodied loupe set from Harbor Freight tools at a low price. They were surprisingly good considering the low price, and a couple of them were high enough in magnification for small but not microscopic pond organisms. Harbor freight still sells these, and I notice t...
by desertrat
Sat Mar 02, 2019 10:45 pm
Forum: Microscopes and optics
Topic: Further tests with repaired Spencer 1.4 N.A. objective.
Replies: 3
Views: 970

Re: Further tests with repaired Spencer 1.4 N.A. objective.

Very impressive images from a repair job that few people could do successfully.

It helps me appreciate my antique 1.25 N.A. fluorite, even though it's not in the same class. I still enjoy using it occasionally.
by desertrat
Fri Mar 01, 2019 11:21 pm
Forum: Microscopy accessories
Topic: Rheinberg Filters
Replies: 7
Views: 7532

Re: Rheinberg Filters

I bought some of this seller's darkfield, circular oblique, and oblique illumination inserts for substage condensers. They are very well made.

No experience with the Rheinberg filters, though. If I plan to try Rheinberg illumination, I would have no problem buying his products.
by desertrat
Wed Feb 27, 2019 12:30 am
Forum: Collecting microscopes and slides
Topic: 1917 Spencer model?
Replies: 13
Views: 2829

Re: 1917 Spencer model?

Adding two small data points: My monocular Spencer microscope with the frame style that was common in the 1920s also has the old style condenser focus mechanism, its serial number in the 57,XXX range dates it around 1920. I have another monocular Spencer microscope with the same frame style and the ...
by desertrat
Mon Feb 25, 2019 1:45 am
Forum: Collecting microscopes and slides
Topic: 1917 Spencer model?
Replies: 13
Views: 2829

Re: 1917 Spencer model?

I have an old Spencer monocular model from the mid 1920s, whose objectives look identical in construction to those. The only difference visible is the lacquer finish is a bit darker on mine. Sometimes those objectives are installed on the 4 Series stand to sort of go joy riding with them. I guess it...
by desertrat
Wed Feb 20, 2019 9:47 pm
Forum: Identification help
Topic: Bacteria
Replies: 9
Views: 2712

Re: Bacteria

You might make a slide from fixated and stained bacteria and show it at high magnification. The light microscope won't show more than the shape though. I once had a look at slides from human bacterial diseases and can remember that the different bacteria arranged themselved in very different ways. ...
by desertrat
Tue Feb 19, 2019 1:18 am
Forum: Camera systems and imaging
Topic: MICAM Settings
Replies: 20
Views: 4537

Re: MICAM Settings

Since everything was set up from the previous session, decided to photograph the diatom with two different objectives. Below, on the left is an AO 43X apochromat NA 0.95, in the middle is an antique Leitz 6L 45X NA 0.65, and on the right is the antique lacquered Spencer 44X NA 0.65 objective used to...
by desertrat
Sun Feb 17, 2019 5:05 pm
Forum: Camera systems and imaging
Topic: MICAM Settings
Replies: 20
Views: 4537

Re: MICAM Settings

...With a small chip camera I would always prefer a lot of light as they tend to break down in low light conditions. So I think that your new solution against the banding creates a new bottle neck in you imaging process. Also the yellow light doesn't make the best use of the sensors capabilities. W...
by desertrat
Sun Feb 17, 2019 4:46 pm
Forum: Camera systems and imaging
Topic: MICAM Settings
Replies: 20
Views: 4537

Re: MICAM Settings

I don't mean to divert your new thread off its MICAM topic, Rick, but may I ask what type of lamp and lamp controller you are using? The incandescent lamp is in the base of my AO 4 Series microscope, and is similar to an old fashioned automotive tail light lamp. It illuminates an optical train in t...
by desertrat
Sun Feb 17, 2019 4:30 pm
Forum: Camera systems and imaging
Topic: MICAM Settings
Replies: 20
Views: 4537

Re: MICAM Settings

Thanks for all the replies. This will give me plenty to work on for awhile. The unsharp mask in GIMP has several parameters that can be adjusted. I guess I need to spend some time to learn how to get the best adjustments with a single application of the mask. I don't mean to divert your new thread o...
by desertrat
Sun Feb 17, 2019 3:03 am
Forum: Camera systems and imaging
Topic: MICAM Settings
Replies: 20
Views: 4537

MICAM Settings

Thanks Bob and Doron for helpful advice on getting and processing images. Doron mentioned MICAM, a freeware microscope image capture program. And Bob has given advice on improving the images with image processing tools. I decided to start a new thread so the existing threads where these were first d...
by desertrat
Sat Feb 16, 2019 9:36 pm
Forum: Camera systems and imaging
Topic: Inexpensive USB 2.0 camera test with two microscope types
Replies: 51
Views: 12424

Re: Inexpensive USB 2.0 camera test

Thanks. Looking at the options you mentioned, I found the menu that allows me to pick the whole 1600 X 1200 resolution this camera can use. It also reduced the frame rate to 2 per second, as you mentioned. This also increased the banding problem to what I had with the Windows XP webcam program. But ...
by desertrat
Sat Feb 16, 2019 8:29 pm
Forum: Specimens, samples and slides
Topic: Some Of My Homemade Permanent Slides
Replies: 31
Views: 7678

Re: Some Of My Homemade Permanent Slides

Hi Bob, thanks for the compliment. The banding is coming from the 60 Hz fluctuations in brightness by the built in illuminator lamp filament being powered by AC. I could eliminate it completely by feeding the lamp with smooth DC. I succeeded doing that in an experiment I posted awhile back. But the ...
by desertrat
Sat Feb 16, 2019 6:58 pm
Forum: Beginner's corner
Topic: Zeiss Axiomat objectives
Replies: 7
Views: 3014

Re: Zeiss Axiomat objectives

Never having seen an Axiomat before, I did some internet image searching. The thing looks kind of like an office copy machine with a binocular viewing head sticking out of one end. Amazing....
by desertrat
Sat Feb 16, 2019 6:52 pm
Forum: Camera systems and imaging
Topic: Inexpensive USB 2.0 camera test with two microscope types
Replies: 51
Views: 12424

Re: Inexpensive USB 2.0 camera test

...The USB camera is controlled with either the Toupview software that came with it (not all camera controls, such as exposure or WB, are supported!), or with the free MICAM software... Thanks for mentioning MICAM! If I had not been just skimming your post previously, I would have seen this much ea...
by desertrat
Fri Feb 15, 2019 4:24 am
Forum: Resources (online, books etc.)
Topic: Book on pond life sampling and pond aquariums in new layout - free
Replies: 14
Views: 3169

Re: Book on pond life sampling and pond aquariums in new layout - free

Hi Bob,

Thanks for posting that! It's obvious a lot of work went into preparing the modern version, and it does have a lot of interesting information.
by desertrat
Thu Feb 14, 2019 11:32 pm
Forum: Specimens, samples and slides
Topic: Some Of My Homemade Permanent Slides
Replies: 31
Views: 7678

Re: Some Of My Homemade Permanent Slides

I like this series of images, a step by step introduction to the structure of the animal, with emphasis is on the findings rather than on the prestige or high class of the equipment. Thanks. No point in me trying to pretend my equipment has prestige. Everyone here knows I'm using old stuff bought c...
by desertrat
Thu Feb 14, 2019 11:26 pm
Forum: Camera systems and imaging
Topic: Inexpensive USB 2.0 camera test with two microscope types
Replies: 51
Views: 12424

Re: Inexpensive USB 2.0 camera test

That's impressive performance for a low cost sensor and reduction lens. The eyepiece camera and .3X reduction lens I bought for somewhat less cost doesn't produce images anywhere near as sharp, no matter how many focus bracketing images I take. My antique objectives are no doubt not as sharp as your...
by desertrat
Thu Feb 14, 2019 7:55 pm
Forum: Specimens, samples and slides
Topic: Some Of My Homemade Permanent Slides
Replies: 31
Views: 7678

Re: Some Of My Homemade Permanent Slides

Please also see the previous post, which has the first four images of this set. The following image, also taken with the antique brass 20X objective, shows the nuclei of two cells with the focus adjusted a little below the surface of the tentacle at these cell's location Hydra_2_20X_c.jpg The follow...
by desertrat
Thu Feb 14, 2019 7:40 pm
Forum: Specimens, samples and slides
Topic: Some Of My Homemade Permanent Slides
Replies: 31
Views: 7678

Re: Some Of My Homemade Permanent Slides

Sometime in late 2004, I succeeded in getting another hydra specimen more or less intact in a permanent mount. This time the hydra was fixed in a hot solution of 2% copper sulfate with about 1/2% to 1% acetic acid derived from distilled white household vinegar which is 5% acetic acid. The hot soluti...
by desertrat
Wed Feb 13, 2019 12:31 am
Forum: Microscopes and optics
Topic: Older B&L microscope question
Replies: 48
Views: 5522

Re: Older B&L microscope question

The top condenser looks like a standard 1.25 N.A. Abbe unit. The lower condenser is a valuable achromatic 1.4 N.A. unit, designed for a specific slide thickness. That much I can see engraved on it. It was designed for high power research work with apochromatic objectives. The upper lens is probably ...
by desertrat
Tue Feb 12, 2019 7:12 pm
Forum: Microscopes and optics
Topic: Older B&L microscope question
Replies: 48
Views: 5522

Re: Older B&L microscope question

Does either of your B&L microscopes have the upper condenser lens buried in the stage? My binocular B&L is set up that way. Only the lower condenser lens moves up and down to focus. Some more photographs might help. The condenser on your trinocular, of which only the lower section can be seen in you...
by desertrat
Tue Feb 12, 2019 2:59 am
Forum: Beginner's corner
Topic: Microbe magazine.
Replies: 2
Views: 1939

Re: Microbe magazine.

It looks like he's trying to link to an article on his hard drive, but it hasn't been uploaded to the forum. And it kind of looks like the article came from the magazine associated with this website.
by desertrat
Mon Feb 11, 2019 4:41 pm
Forum: Off Topic
Topic: Comet Iwamoto Ascends and Brightens..
Replies: 2
Views: 2684

Re: Comet Iwamoto Ascends and Brightens..

Thanks for the link! Will be following the comet's progress there. It's going to be mostly cloudy here for the next week at least, with some rain and snow.
by desertrat
Mon Feb 11, 2019 4:29 pm
Forum: Pictures and Videos
Topic: Amphipleura Pellucida Striae
Replies: 6
Views: 1053

Re: Amphipleura Pellucida Striae

Thanks, Bob and 75RR! I forgot to mention in the first post that the oil immersion dark field condenser has one additional advantage. The illumination can be fairly easily adjusted between extreme oblique, and circular oblique illumination. The extreme oblique illumination from off one end of A. Pel...
by desertrat
Sun Feb 10, 2019 8:56 pm
Forum: Beginner's corner
Topic: USB camera issues
Replies: 9
Views: 2512

Re: USB camera issues

The cheapest eyepiece cameras have no optics in them at all, besides an IR/UV cutting filter. I have one of those. The sensor is set for the intermediate image from the objective to fall on it. If the objective needs to be used with a compensating eyepiece, the compensation doesn't happen, but the i...
by desertrat
Sun Feb 10, 2019 8:51 pm
Forum: Home-made microscope adaptations
Topic: A Couple of Fittings for the 4 Series Microscope
Replies: 18
Views: 5582

Re: A Couple of Fittings for the 4 Series Microscope

Hi Bob, Some American lathes are designed to be fitted with a 127 tooth conversion gear that allows for exact conversions to metric threads. My old Atlas lathe wasn't designed to use that. For it, some extra gears used in the quick change box can be bought and are fitted to the movable quadrant outs...
by desertrat
Sun Feb 10, 2019 8:31 pm
Forum: Pictures and Videos
Topic: Amphipleura Pellucida Striae
Replies: 6
Views: 1053

Amphipleura Pellucida Striae

This is one of the diatoms in Klaus Kemp's 8 form test plate, and the most difficult to resolve beyond the exterior shape. Over ten years ago I tried to see details inside with an oil immersion objective, but the best I could see was very faint hints of striae that might have been imaginary. I had a...
by desertrat
Sun Feb 10, 2019 6:55 pm
Forum: Home-made microscope adaptations
Topic: A Couple of Fittings for the 4 Series Microscope
Replies: 18
Views: 5582

Re: A Couple of Fittings for the 4 Series Microscope

Digital readout, dial or vernier calipers can quickly and accurately measure the pitch on ANY thread.. BillT That's a very good point, and one I didn't think about. But because of the ledge right next to the threads on the filter and the shape of my dial calipers' jaws, I probably wouldn't be able ...
by desertrat
Sun Feb 10, 2019 6:48 pm
Forum: Home-made microscope adaptations
Topic: A Couple of Fittings for the 4 Series Microscope
Replies: 18
Views: 5582

Re: A Couple of Fittings for the 4 Series Microscope

I wonder. At one time I had a circular ND glass filter, without a metal sleeve, just the bare glass, installed in a general-purpose Newport or Oriel round filter holder. When placed on top of the illumination port, there was a vertical distance of about 10mm (roughly) between the filter and the por...