Jump to content

sgl_imaging_challenge_2021_2.thumb.jpg.72789c04780d7659f5b63ea05534a956.jpg

ftherrmann

New Members
  • Content Count

    24
  • Joined

  • Last visited

Community Reputation

0 Neutral

About ftherrmann

  • Rank
    Nebula

Profile Information

  • Location
    Hsv AL
  1. ftherrmann

    Fred's Astrophotography

    Variety of DSO images taken from the backyard observatory
  2. PS: You will also see a slight bit of sag using a large/heavy CCD like the STL with the 85. I had a fully threaded optical train and still saw some slight differences at 0 and 90 PA due to the chip sagging non-orthogonal to the optical axis.
  3. I own both the FSQ-106 (old blue label) and a TOA-130. Never had any problems with either other than the fact that the TOA-130 w/flattener will not produce a flat field using the STL chip. Works fine with 8300 and smaller chips. I didn't try the 8300 with the 85 @3.6 but I kind of wonder if it would flatten to the edges of the 8300.... No I didn't get a lemon. Land Sea and Sky sent me a 2nd reducer/flat to try and it produced the same results at 0 PA and also 90 PA. The defocused star at the center of the fov was perfectly round, ie collimation was spot on. The 85 simply won't work with
  4. Just saw the spec for the 85 with reducer..... With reducer .75x - Image circle 40mm I notice it doesn't say "Flat" unlike the 85 OTA description. However like I said.... It doesn't come close to 40mm. Illumination isn't a problem. The edges were 60% illuminated when compared to the center of the fov. Also the .75x reducer isn't correct. It's actually a .73x reducer.
  5. Yes I know that the image is under-sampled at 5.6"/pix. However I don't really care that much about that part of the story. Unless you zoom in 400% your not going to notice the under-sampling. However you do notice the coma shaped stars w/o any zoom. As far as the specs are concerned here's a cut and paste from the "Land, Sea and Sky", aka Tak America webpage: -Flat field w/60 mm image circle -Image circle will accept medium format CC cameras or Digital SLRs The 85 + reducer combination doesn't come close to either a flat 60mm circle or 40mm circle as the stars at all edges and corners
  6. Brand new and it was all returned to the vendor for refund.
  7. Just wanted to jump in and say that after 4 nights experience with the FSQ-85 /w .73 reducer and STL11K I was unable to obtain anything close to a flat field. I was also sent another replacement reducer which gave the same poor results. My Nikon 200mm telephoto produces a flat field as good or better than the FSQ-85 w reducer. Very disappointed. The FSQ-85 gave a perfectly colimated defocused star at center field. Rotating the CCD/reducer 90 degrees gave the same results. I've seen some images made with the new FSQ-106 and .73 reducer which looked almost perfect. Any experience out th
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.