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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5563941 - 12/10/12 10:58 AM Attachment (19 downloads)

Second

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5563946 - 12/10/12 11:00 AM Attachment (17 downloads)

Third

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5563947 - 12/10/12 11:01 AM Attachment (21 downloads)

Forth

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5563959 - 12/10/12 11:07 AM

Just taking one image in green will yield a good image when greyscaled. OK for the Moon, for instance, The system being monochromatic is not constrained by the low power initiative, and very high powers can be used.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5563985 - 12/10/12 11:26 AM Attachment (22 downloads)

Ed here is a full colour image taken wuth a six inch Hypo, a bit unsharp, but the camera is not up to it.

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GlennLeDrew
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5564062 - 12/10/12 12:17 PM

What is the focal length and aperture if the camea's taking lens? If a small-format point and shoot, the aperture (for daylight exposures, and when not zoomed in much) might be as small as about 1mm. This will effectively stop down the telescope if the exit pupil is larger.

For example, an 8mm f.l. lens at f/8 would have its aperture stopped down to 1mm. If the scope's exit pupil were to be, say, 6mm, that 150mm aperture would be effectively reduced to 1/6, or a mere 25mm. This will offer dramatic improvements in aberrations.

This is one of the dangers of afocal imaging. And I contend that the camera is well up to the task of representing what it 'sees', as long as it's reasonably well centered and positioned, and not shaking during the exposure. If the camera is so bad, all other 'normal' snaps would be poor, too.


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MKV
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5564184 - 12/10/12 01:21 PM

Quote:

Forth



So, you have to adjust the size as well? Nice photo art.


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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: MKV]
      #5565765 - 12/11/12 11:27 AM Attachment (24 downloads)

I switched to internal imaging techniques by fitting a 5 inch 60 inch focus refractor lens in front of the Hypo system up on test. I could place images close to the bench and control them. The first image is the optical layout of the system. This hypo array uses an achromatic reduction lens. The test is to qualitatively assess the amount of colour aberration in the images.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5565767 - 12/11/12 11:30 AM Attachment (21 downloads)

The second image is an artificial solar disc with an outsize spot, this to test a black and white image

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5565771 - 12/11/12 11:32 AM Attachment (21 downloads)

Note residual colour fringes typical of the Hypo system. The third image is of a brilliant star cluster.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5565774 - 12/11/12 11:36 AM Attachment (25 downloads)

Final image is to shew the amount of colour in a pattern of bright spots, these are RBG mix LED lamps, this colour aberration is the amount encountered with a Hypo.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5565779 - 12/11/12 11:38 AM

Mark, I now withdraw from the Arena

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ed_turco
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5565968 - 12/11/12 01:39 PM

Why do that; I'm very impressed with the new pics; very impressed!


Ed


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GlennLeDrew
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Re: Hypo/Dialyte testing discovery new [Re: ed_turco]
      #5566163 - 12/11/12 03:42 PM

With the new series of pics, we still need to know the diameter of the camera lens's aperture with respect to the exit pupil under test. If the iris is smaller than the exit pupil, the system is stopped down and so performance will be artificially improved.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: GlennLeDrew]
      #5567162 - 12/12/12 08:55 AM Attachment (12 downloads)

OK Ed here are a few more, these are all artificial images, IE illustrations from glossy mags, and in the case of the moon a picture post card, now these images suffer as a result of this reproduction. The intention is to see how various images are affected by the colour aberration, extended images show very little or none, re the moon and the ring neb, yet the star images shew colour splitting. Jupiter is another pic from a well known astromag, and here again the extended image shows little or no spurious colour Now I have seen colour splitting in images taken with SC scopes just as bad as the stars shewn here.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5567165 - 12/12/12 08:56 AM Attachment (10 downloads)

Next

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5567169 - 12/12/12 08:57 AM Attachment (10 downloads)

finally

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5567176 - 12/12/12 09:01 AM

MKV. I had to downsize the image to suit reqirements laid down, I would be happy to shew the tree larger than this.

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Crayfordjon
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5567207 - 12/12/12 09:28 AM

Glenn I have not a clue what size the camera lens is, as it is buried deep inside the digital, hard up against the detector. Most cameras these day have lenses which are nothing more than glorified pinholes, gone are the huge lenses we enjoyed on the old SLR film cameras, I know the more expensive and hugely complex digital cameras have larger lenses, but they are out of my league. For all that the ordinary run of the mill digital produces marvellously good images for general use due to the efficiency and high resolution of the imaging chip. Now what you say is true, a one mm aperture will cut down the OG quite a lot, but all of it is still used. Complex camera lenses are stopped down in varying amounts to suit light levels, never is the full wide open lens system used, (some do perhaps ), With the Hypo system I am using, the OG is stopped down but look at it as a camera lens and not a telescope in the way we use them for visual work. You might say why use a full aperture if it is only going to be used at one third aperture, so lets only use a smaller diameter OG, this does not work in the same way as leaving the system at full aperture, where as I said before, although it is stopped down, you are still using the full aperture, as it scans the full field of view. Incidently, binoculars, generally have an exit pupil of around 5mm, yet we use them in the daytime when the average human pupil is only 2 to 3mm. Everybody accepts this quite happily, as long as you can see the type of tail feathers a lesser spotted twit is displaying, it dont matter

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kfrederick
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Re: Hypo/Dialyte testing discovery new [Re: Crayfordjon]
      #5567232 - 12/12/12 09:42 AM

It images nice that is all that matters. Congrads John for this design. Mark will push the design and learn some . All good . To have a big single lens telescope is what ATMs dream off .

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