The focal length is a bit over 600mm. I use a barlow, so the focal length is around 3000mm effective. The images are from Astia 100f (35mm), scanned on the Minolta 5400 II, but reduced by two.
Obviously, the image is tweaked quite a bit in photoshop. The raw image is very blue. I use a long pass filter (optical) to reduce some of the haze. A bit more OT, but I've discovered that so called UV filters don't really remove much UV. I have a flashlight made of 380nm UV leds, which I use as a test source. If you aim the UV at a phosphor screen (such as an oscilloscope), the screen will glow. This allows me to make a crude UV filter test. The run of the mill camera lens UV filters are a joke. My glass is from Andover, and it really kills UV. [Haze is inversely proportional to the fourth power of the wavelength, so a little filtering helps a lot.] Schott Glass makes two UV filters in camera rather than astronomical sizes. I plan on getting one of these for use in high altitudes, where UV is really strong. James L. Sims wrote: >Ah, but you're redefined the scope of reach! Just how long is the lens >you used for this project? Or, just how small is your sensor? I can see >that you don't need high spatial frequency, scintillation pretty much >wipes out resolution at that distance. Great job though! I am >surprised and impressed at the detail you captured at that distance. > >Jim > >[EMAIL PROTECTED] wrote: > > >>I have a Tak FS78 and quite a few accessories for such antics, but you >>can't use them on the fly. This is a panorama I just finished last week, >>with the distance varying from 15 to 20 miles. >> >> >> >> >>>http://www.lazygranch.com/images/ttr/june2007/ttr_pano_1.jp2 >>> >>> >>> >>You will need a jpeg2000 viewer such as irfranview. >> >>I didn't bring up the term "reach", so I wanted everyone on the same >>page. I'd like it to be the case that less is more when it comes to >>sensors. >> >> >>Arthur Entlich wrote: >> >> >> >> >>>Based upon what you are shooting, you don't need "reach" you need a spy >>>satellite ;-) >>> >>>It all comes down to how much you want to pay, how much weight yo want >>>to lug, and how long the lenses are you wish to carry. Have you >>>considered a Telescope? >>> >>>Art >>> >>> >>>gary wrote: >>> >>> >>> >>> >>> >>> >>>>I'm a person that needs "reach", if you define reach as getting shots of >>>>distance objects. Now generally a person who needs reach is using a >>>>telephoto lens and possibly combined with a teleconverter. Such a setup >>>>doesn't put out a lot of light, so the bigger pixels are certainly an >>>>advantage. Also, I've been told that even if noise was not an issue, you >>>>can't simply keep reducing the pixel pitch due to difficulties in lens >>>>design. If anything, a 10um pitch would be optimal. >>>> >>>>http://www.lazygranch.com/groom_lake_birds.htm >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >> >> >> >> >> > > > > ---------------------------------------------------------------------------------------- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
