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Posts Made By: Joplin Motisher-Chittenden

May 22, 2003 07:17 PM Forum: Equipment Talk

Question about Field Stops

Posted By Joplin Motisher-Chittenden
It limits the field of view and also serves as a baffle against stray light. Without the field stop the edge of the field of view in most eyepieces yields a poor quality image along with an gradual and annoying fall off of the image rather than a well defined circle edge.

Joplin

May 26, 2003 08:16 AM Forum: Equipment Talk

Levelling cg5 - newbie

Posted By Joplin Motisher-Chittenden
Jay,

I would suggest that you try leveling the tripod without the mount attached to it. It will be much easier without the weight of it bearing down on the tripod. I wouldn't worry about getting it perfectly level, just reasonably close. When the manual refers to turning the altitude adjustment screw clockwise/ counter clockwise it is refering to the screw at the back underneath the polar alignment scope eyepiece (opposite the side with the counterweight). When you need to adjust the altitude setting back off the screw on the side towards the counterweight (it just locks it down). Then you can adjust the screw the manual refers to. When you need to move the mount to a higher altitude setting it may help to pull up a bit on the counterweight shaft while turning the altitude adjustment screw clockwise. When you are done adjusting it, go ahead and lock the screw opposite from it back down.

Joplin

May 27, 2003 07:50 PM Forum: Birding Optics and Photos

Is it safe to come out ?

Posted By Joplin Motisher-Chittenden

May 27, 2003 11:07 PM Forum: Wildlife Photography

Flower??

Posted By Joplin Motisher-Chittenden
Looks like a type of Spiderwort flower. I am by no means a flower expert but I used this cool site to arrive at that conclusion:

http://www.acm.org/pubs/tog/editors/erich/flowers/flowers.html

I entered as much data from your image as I could and came up with 4 possibilities, one of which was the Ohio Spiderwort (identical looking besides color). This site is for wildflowers so I doubt it will be very useful on bred and cultivated flowers.

Joplin

May 28, 2003 10:57 PM Forum: Equipment Talk

115 f7 focus

Posted By Joplin Motisher-Chittenden
You probably just need a diagonal or extension tube. Just a guess but is this one of the TMB/ APM apo's ? I think those scopes are designed with a generous amount of backfocus for imaging and binoviewing purposes and would most likely require an extension tube to reach focus without a diagonal.

Joplin

May 31, 2003 08:07 PM Forum: Equipment Talk

10" dob eyepiece 6mm range

Posted By Joplin Motisher-Chittenden
The best option would be a 6mm Televue Radian in this focal length, but it costs over 2.5 times as much as your upper price limit, even used. Other options would be the Vixen LV 6mm and the Apogee Super Easy View 5.5mm which both have relatively small fields of view (45 degrees or so). A good low cost option would be one of the Orion Expanse 6mm (relatively wide 66 deg. fov and decent eye relief for 50 bucks new).

Joplin

June 3, 2003 06:24 PM Forum: Equipment Talk

Pentax XL Eyecup removal

Posted By Joplin Motisher-Chittenden
I don't know if it can be removed but I doubt that it would be very easy to get it back on if you did remove it. My solution for my 7mm Pentax XL was to make an adapter out of PVC plumbing tubing, two step rings and some sheetmetal screws. Total cost was about $15. It simply slides on over the eyecup (pretty snug fit so there is no chance of it coming off by accident). The eyecup is still adjustable to minimize vignetting and get the camera lens as close as possible to the eyelens. I get zero vignetting with my coolpix 995 even at the wideangle setting. I can post a couple pictures and details on the parts I used if you want.

Joplin

June 6, 2003 04:57 PM Forum: Equipment Talk

Planetary views, collimation, sample (me again)

Posted By Joplin Motisher-Chittenden
Ron, I've seen views that approach the level of detail (not as much contrast) during very good seeing conditions with my 10" F6 Parks Newtonian. I've attached a modified version that is more representative of what I can see at the eyepiece on an average evening when jupiter is still high in the sky (it's too low now). Also, you don't need to use 272x to get a good level of detail on Jupiter. On an average night 200x will be more than enough with a 6" reflector. Saturn can usually take more magnification since it has higher contrast features.

Joplin

June 7, 2003 03:55 AM Forum: Birding Optics and Photos

If you don't mind...

Posted By Joplin Motisher-Chittenden
Christine,

I do most of my bird photography in my backyard. Lately I've been watching a Red Bellied Wookpecker use a dead tree in the backyard for a home. I use most of the equipment I have for astronomy as well as birding. There seem to be several general categories of equipment used by birding photography enthusiasts. The most common technique is to use a spotting scope and digital camera. The camera is either held to the eyepiece with the scope on a tripod or mounted via various adapters. Since there are so many astronomers on this forum, telescopes that serve dual purpose for astronomy and birding/ wildlife are used quite a bit in place of spotting scopes. Last, there is the group that uses top of the line digital SLR cameras, either with telephoto lenses or mounted on scopes. Film has fallen out of favor in many cases since digital cameras offer quicker results. Anyway, here is a photo of my setup for birding photography (Vixen FL80S refractor on sturdy fluid panhead and tripod with all other equipment attached except the digital camera)

Joplin

June 7, 2003 08:14 PM Forum: TeleVue

7mm Nagler & 9mm Nagler EPs

Posted By Joplin Motisher-Chittenden
I've looked through some of the Orion Epic eyepieces, a Televue 11mm plossl, 9mm type 1 nagler, and 7mm type 6 nagler at various times. The Naglers have an immense field of view compared to Plossls and the Epics. The Naglers have a bit more eye relief than the plossls, but not nearly as much as the epics and other long eye relief designs like the Radians and Pentax Xl's. For the greatest view quality / comfort combination, I like the Pentax XL eyepieces with the radians close behind. For a huge field of view and medium amount of comfort while maintaining high image quality, the Type 6 Naglers are the best (at these focal lengths). I found that I prefer my 7mm Pentax XL compared to a 7mm Nagler Type 6 because of the increased viewing comfort. I found that taking in the whole field of view in the 7mm Type 6 required pressing my eye too close to the eyepiece ( I think my eye sockets are pretty deep though :-)

Joplin

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