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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

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  1. tjd

    Tempted

    Hi all, Regarding your earlier question DIY171, regarding the larger aperture able to achieve a better resolution and power, the answer in theory is yes, and yes. Because the larger objective will let in more light, (2 ¼ times more light according to Musoman ), and also because, in theory, the...
  2. tjd

    Celestron C5 + Canon 550D

    Hi Pete, I believe that the reason the highlights below the beaver are not showing the ring effect is because most of the highlights in this area are in focus,...the ring effect only appears at out of focus points. Hi Stefano, Nice shooting, was going to buy a C5 myself some years ago, so...
  3. tjd

    A surprising observation (well, to me, anyway)

    I find that quality of image can certainly be acceptable when shooting through modern window glass, which is much much flatter than it used to be years ago. Especially if you shoot square on, as Paul says, and also pick your spot...trying different parts of the window. To avoid the turbulence...
  4. tjd

    Astroscope + DSLR = Gallery!

    Hi Cridl Nice moon-shot, with a good exposure and contrast, moon is often printed too harsh. ........................... tbc Glad to see you were able to upload in the end, I am also using Internet Explorer and cannot upload to this forum...the reply area does not even show the `manage...
  5. tjd

    At last....

    Great Idea Great ideas guys, .....my own equipment should be up and running soon ( Revelation ED80 ) and I would hope to contribute to gallery when ready. May I throw a name into the hat......`Prime Focus Gallery` and if any possible new thread is attached it could be called`Prime Focus...
  6. tjd

    TS optics TL APO 804, a small review.

    The simple and low cost alternative to Fernando`s high quality diaphragm may be obtained from the lens unit of an old bellows camera. This is what I am experimenting with at present. The largest opening diameter being around 20mm. Just dis-assemble from original lens and solder on an extension...
  7. tjd

    TS optics TL APO 804, a small review.

    Fernando, Just another couple of points that may be relevant to throw into the pot.! Firstly, from my meagre knowledge of astro use, most of these flatteners are optimised for use at infinity/the stars, and therefore is it possible that you, when using for an image of a bird at 30 metres, are...
  8. tjd

    Comment by 'Guest' in media 'Steady arm for tripod'

    Thanks Peter, It is not a Televue, It is a Revelation 80ED, which I believe is made in the Synta optical works, and similar to the other good quality 80ED`s under different brand names. It is very similar to the Williams Zenithstar. I am very pleased with it Am in the process of getting it up...
    • tjd
    • Gallery comment
  9. tjd

    New tripod

    Thanks, The fixing points for the ends of the arm are a bit of a compromise. I was going to attach to front of scope to give more stability, but then more awkward to use quickly. I see the Manfrotto fixes to the focus tube or camera support, which of course gives great stability but maybe...
  10. tjd

    New tripod

    Hello Thornly, Sorry, but I cannot post images here because of some weird way my computer is linked up, but see here, in my gallery for photograph and description of steady arm. http://www.birdforum.net/gallery/showgallery.php/cat/500/ppuser/70526 Arm has quick release or lock, or just lock...
  11. Steady arm for tripod

    Steady arm for tripod

    Velbon DV7000 tripod, with home made steady arm. Arm has quick release or lock, or just lock enough to give a smooth steady elevation. Once locked, scope can take more weight, even if out of balance, and even though locked a fine screw height adjustment is still available via knurled collar...
    • tjd
    • Media item
    • steady tripod
    • Comments: 2
    • Category: Equipment And Accessories
  12. Rook? in frosty tree

    Rook? in frosty tree

    Rook? in frosty tree
    • tjd
    • Media item
    • frost snow
    • Comments: 3
    • Category: Britain & Europe
  13. tjd

    New tripod

    I,m fairly happy with my tripod, (now I`ve added an adjustable steady arm ) It`s a Velbon DV7000 with fluid head, which is intended for video camera work, but also makes panning and height adjustment beautifully smooth for the scope. Has clamps for each movement. Can be bought for around...
  14. tjd

    Example with a 90mm Maksutov-Cassegrain type scope

    lack of contrast I agree that the images on the web-site taken by the Mak. Cass. do suffer from a certain dullness/flatness. . The reason behind the particular glare that causes the...
  15. tjd

    Example with a 90mm Maksutov-Cassegrain type scope

    The main problem with reflecting scopes rather than refractors, from my experience, is that they hve less contrast, and more glare when used terrestially, compared to a refractor. This is because of two main reasons. 1/.... a small decrease in contrast and resolution is caused because reflecting...
  16. tjd

    Possible alternative to barlows/teleconverters

    Excellent for sharpness Paul, I think possibly your sharpest image yet, especially from 30 metres. And not a trace of C.A.I am also experimenting at the moment and was checking out available lenses from a Praktica 80 to 200mm zoom...
  17. tjd

    Fancy a 500mm f3.25 ED

    I`m sure that such a short focal length front element was designed to always include the second element in train to reduce abberations and to achieve the perfect image. Therefore larger element is not likely to produce a good image on its own.The second (negative ? ) will of course extend the...
  18. tjd

    Fujinon CE20-1 2X teleconverter (Nice)

    I am happy to accept this for the benefit of the two seperate magnifications. I can mark the diopter adjustment wheel with the two seperate positions and just dial in as needed (hopefully).....we`ll see ! Tom
  19. tjd

    Fujinon CE20-1 2X teleconverter (Nice)

    Hi all, As I write this I await delivery, (from a slow boat from China ) of a 1.25x / 2.25x right angle viewer made by Seagull and will post again when I check it out.Cost £25...
  20. tjd

    Possible alternative to barlows/teleconverters

    Hi Thornly,As in my previous post, the ideal position for the baffles should take account of the most used position of the field lens. And then on top of this the field lens itself should also carry with it, it`s own set of baffles, sliding along with it.Further to this and a point often...
  21. tjd

    Possible alternative to barlows/teleconverters

    Apologies to all,Everything was clearly in paragraphs before I pressed submit button.??Tom
  22. tjd

    Possible alternative to barlows/teleconverters

    Hello Alphan,After following the exploits of the forum recently, and having created baffles on a few optical instruments over the years, I hope my experience is helpful, as follows.With regard to a scope type such as the 80Ed, where you are adding various internal lenses, the first thing to make...
  23. tjd

    Stopping down with modified diaphragm

    Chris B.No need to spend 99 dollars, one from an old bellows camera will do the trick...around 20mm max. dia. opening. Just extend the operating lever by soldering on a small brass extension.Tom
  24. tjd

    Stopping down with modified diaphragm

    Musoman,,Re your question, "Wouldnt it mean cutting a slot in the focus tube to allow the aperture lever to poke through ?"... I have done this to my scope, cutting a slot in the top of a 2" extension tube, and it works very well (see my post of 31st August, but still am unable to be able to...
  25. tjd

    Stopping down with modified diaphragm

    Dear all, I hope it is OK with you all if I add a comment or two regarding the use of diaphragms, but I have been reading your very interesting technical conversation on the use of diaphragms etc and I would like to contribute my own findings from my own recent experiences, and hope they may...
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