![[Home!]](../../images/mighty_etx.jpg){kind=small}
Last updated: 31 August 2007
|
Last updated: 31 August 2007 |
Subject: Commercially available T-ring & T-adaptors?
Sent: Monday, August 27, 2007 08:30:07
From: Bobby Meyer (bobbyp416@msn.com)
As others have done before me, I wish to thank you for a very
informative and useful site for us ETX owners! I have learned many
things about my scope and Autostar simply by reading other readers'
questions and comments.
I am the proud owner of a Meade ETX-90/EC (and a MUCH larger 10"
Meade LX-50 SCT). I have recently purchased a Canon EOS 350/D camera,
and am interested in trying my hand at prime focus and eyepiece
projection astrophotography through both of these fine instruments.
Planetary images are at times excellent through the ETX, and I would
like to take advantage of the digital SLR's high- speed capabilities.
I am, however, a little confused at the availability of commercially
sold T- rings and T- adaptors for this particular model of camera.
Are there any out there? Perhaps you (or other readers) can answer my
question?
If so, what sort of balance problems can I expect when coupling my
SLR to the ETX? How do I offset for the camera's weight?
I look forward to hearing back from you, and will continue to check
on your fine site for more useful information in the future.
Thank You,
Bob
Bob Meyer bobbyp416@msn.com
Mike here: I'm sure there are T-Ring Adapters for the Canon DSLR; check your camera dealer. T-Rings connect to the various astrophotography accessories. As to balance, you may or may not have a problem, depending on the telescope. I don't have a balance problem with my Nikon D70 DSLR attached to my LXD75-8"SC nor to my ETX models (except the ETX-70). If you do have balance problems you can make a counterweight (see the Helpful Information: Astrophotography page for lots of tips). Also, with the ETX you will find that the fork arms will prevent a full range of movement if you mount the camera at the rear port.
And:
Thanks for getting back to me so quickly!
Sometimes I have to look up and say 'Thanks' for not making my head
self- detachable, because I may just forget where I've laid it!
I have since gone to a reputable camera dealer in the area and found the
T- ring I was looking for.
Thanks for the 'heads- up'.
Best Regards,
Bob
Subject: Comet C/2006 VZ 13 (LINEAR) and planet Mars Sent: Saturday, July 14, 2007 14:45:48 From: Peter Rosen (rosen@pixmix.a.se) I have taken my ETX-105 from the fork mount and put it on a SkyWatcher HEQ-5 Pro mount instead, so it can carry heavier accesories and track for longer exposures. The sky does not get dark up here in Stockholm - Sweden at this time of the year but I wanted to give it a try and photographed Comet C/2006 VZ 13 (LINEAR) on the 14th of july at 01:20 local time.I choose 7 shots and stacked them in Photoshop into 2 separate files, one where I aligned the stars and removed the comet, and one where I aligned the comets head and removed the stars. I then merged the 2 files again. Canon Eos 20D at prime focus, 7 x 45 sec at 1600 asa. I also had a try on Mars that is still low on the horizon and only 6.6" wide. There are some duststorms hiding the south polar region, so very little surface texture is visible but as the planet will get higher in the month ahead and grow to 16", I expect some better shots. I also put in a picture of Mars from Starry Night Pro as a reference.
Canon Eos 20D through a Takahashi LE 5mm eyepiece, 1/3 to 1 sec exposure at 400 asa, stacked 10 shots in Photoshop. Sincerely /*Peter Rosen
Subject: Astrophotography with Canon Digital SLR Sent: Tuesday, May 22, 2007 14:47:44 From: jbg13@alu.ua.es (jbg13@alu.ua.es) I intend to try out my Meade ETX125PE with my camera digital SLR Canon EOS 400D just bought in UK: I would appreciate information from those having experience with the same equipment in particular about 1/- differences in image quality, object ( deep sky , planets) and focusing ability when attaching the camera with its Canon T Ring to either prime focus or an eyepiece projector adaptor 2/- the Revelation Eyepiece Projection and Prime Focus Camera Adaptor I bought from Telescopehouse UK: T adaptor for prime Focus Use is OK, BUT using the 70mm extension tube, I find that my 1.25" Meade Super Plossl 26mm EYEPIECE CAN'T BE FITTED INSIDE THIS EXTENSION TUBE and so, the eyepiece locking screw of the extension tube seems irrelevant. My 1.25" Meade Plossl 14mm eyepiece can be fitted inside the extension tube BUT NOT entirely because the last 4 mm are too wide. Doing so, it would appear the camera pivoting mirror is going to be too close, even dangerously, to the eyepiece. My 1.25" 9mm Meade Plossl eyepiece can be fitted inside the extension tube BUT NOT entirely because the last 4 mm are too wide. Doing so, it would appear the camera pivoting mirror is going to be too close, even dangerously, to the eyepiece. Also the eyepiece is too short to be locked with the screw inside the extension tube. Thank you every one jeanine
Subject: mounting a canon 20d onto a meade etx-125 Sent: Saturday, May 19, 2007 06:35:27 From: mike foy (mike@foy.com) about mounting a canon 20d onto a meade etx (125) I have a t-mount and meade 64 connection, but it seems to be the camera needs to be much closer to the telescope in order to focus. could you please tell me how you mounted the 20d for your fine photographs thanks mikeMike here: I don't have a Canon 20d; I do use my Nikon D70 DSLR. You can see my comments on using it for astrophotography on the Helpful Information: Astrophotography page. If you search the Site for "Canon 20d" you will get several "page hits" with information.
And:
thanks, didn't realise that the focus know on the meade, moves the mirror back and forth, I thought it just moved the eyepiece up and down, so using a t-mount and meade connected AND the focus knob, I managed to get things in focus. thanks for getting back mike
Subject: size Sent: Friday, April 20, 2007 14:45:31 From: shirley m feickert (sfeickert@earthlink.net) I just bought a Canon EOS Digital Rebel 6.3MP SLR Camera w/18-55mm Lens and also a bought SIGMA DL Macro Super 70-300mm AF Zoom lens is something I can use for Astrophotography (deep sky)? JIMMike here: Yes, you can attach the camera piggyback to a polar mounted telescope and take long duration exposures through the camera lens. Use the telescope to track the sky and make any manual guiding corrections (I use an illuminate reticle eyepiece for this although a high power eyepiece will suffice). You can also attach the camera to either an eyepiece projector adaptor or to prime focus and take shorter duration photographs through the telescope. I recently purchased a Meade Off-Axis Guider that I've been using with my Nikon D70 DSLR (report on my LXD web site). I recommend you get a wireless remote (assuming there is one for th Canon) and set the camera to "Bulb" when taking long duration exposures. Then use the "hat trick" method for the actual exposures.
And:
is 6.3MP good enough for deep sky? I do not understand about pixels. Sorry about the last e-mail on the short subject line. JIMMike here: Many imagers and digital cameras have less, so yes, it should be fine. My Nikon D70 is a 6 megapixel camera and I use it for astrophotography as you can see on my sites. Others use the Canon Rebel, as seen on the ETX Site.
Subject: Advice/Info needed on Astrophotograthy using Cannon EOS Rebel XTi Sent: Wednesday, March 7, 2007 15:33:19 From: Yan, Zhaohui (zhaohui.yan@intel.com) I started reading your website today and realize this is exactly the kind of source I am looking for recently. Quick and general question for you: I have a Mead ETX80-BB (the portable one) and a Cannon Rebel XTi dSLR and am interested in getting into the wonderful world of digital astrophotography. In your opinion, do you think the equipment I have now will allow me take astro-photos for things like Jupitor, Saturn, Mar, etc? Any specific additional equipment I need to buy? Let me know. Thanks! Zhaohui YanMike here: Well, you may be able to get some photos but you should be aware that the camera might be too heavy for the ETX-80; my Nikon D70 DSLR is too heavy for my ETX-70. Slippage can occur during the exposure, ruining your image, since the axis locks have limited friction to hold the extra weight. That said, you might be able to use the camera piggyback for wide field astrophotography. Keep in mind that for long duration exposures you will need to mount the telescope in polar mode. For the planets the exposures will be shorter and so you can get away with mounting in Alt/Az. If you want to try mounting the camera to the eyepiece there are adapters to do that (see the Accessory Reviews: Astrophotography page as well as the Helpful Information: Astrophotography page). You may also want to consider building a counterweight system if the camera is too heavy and slippage occurs. There are many articles on counterweights on the Helpful Information: Astrophotography page as well as a Canon DSLR feedback section. One last point: you will see many references to Scopetronix adapters. These are great but unfortunately Scopetronix has been going through a lengthy transition period and many purchasers are experiencing shipping delays on ordered products.
And:
Thanks a lot for the advice and information. What is the meaning of "mounting in Alt/Az" and "camera piggyback"? Sorry for my ignorance in this field. I think for me, the 1st thing I would like to do is to be able to shoot some photos of the Moon, I am assuming slippage is not an issue (please advice) since you can pretty much using manual control rather than the autostar. ZhaohuiMike here: The ETX-80 (and many other ETX models) are mounted normally in Altitude/Azimuth mode. This means that the telescopes moves in both axes to track objects in the sky. Piggyback means to attach the camera to the telescope tube and use the telescope for tracking/guiding but use the camera and its lens to take photographs of the night sky. One other thing to keep in mind, especially with DSLRs (and film cameras too) is that vibration will be induced when the camera's mirror and/or shutter moves at the start and end of the exposure. This will ruin your image. To avoid this happening you should cover the telescope (or camera lens, if piggyback), open the shutter (via the Bulb setting), flip the cover out of the way for the duration of the exposure, then cover it again, and then close the shutter. This will avoid those vibrations. If your camera has a remote cable or wireless release you should use that. If not, then use the self-timer (assuming the camera has that).
Subject: RE: Camera too heavy?? Sent: Thursday, February 15, 2007 19:51:21 From: Eric Rosenzweig (zweige@cox.net) Thanks for the advice. Much appreciated. Any feedback on the advice I got from Scopecity regarding NOT to buy the UHC filter?Mike here: Typically these types of filters work best on larger aperture telescopes. However, depending on your observing conditions you may get some benefit from one. For more on broadband, narrowband, and light polution filters, see the Accessory Reviews: Filters page.
Subject: Camera too heavy?? Sent: Wednesday, February 14, 2007 20:25:16 From: Eric Rosenzweig (zweige@cox.net) I recently bought a Canon XTi Digital SLR camera and wanted to try it out on my 105-PE. So, I got a T-ring and a Lumicon camera adapter that goes into the eyepiece tube. It's the one where you can either use the bottom part right to the T-ring, or use the whole tube and put an eyepiece in the tube (I attached a picture from the Lumicon website). Anyway, I've found that the weight of the camera tends to weigh the tube down so that it gradually tilts the front of the telescope up. The adapter itself isn't too heavy, but with an eyepiece inside of it, plus the camera seems to really weigh it down. The only way I can correct this is to really tighten down the fork. So three questions:Mike here: You need to add a counterweight to maintain the balance. There are several ideas on the Helpful Information: Astrophotography page. Yes, you can damage the locking mechanism by overtighting the axis locks. The way you mount the camera for prime focus or afocal photography will work. Alternatively, you could attach the camera "piggyback" and do the photography that way. As to the eyepiece, the problem with using an eyepiece is the size AND the magnification you get at the image plane. You won't be able to use the longer focal eyepieces for just the reason you state. PLUS you will have tracking problems except for short exposures on bright objects. And don't forget to avoid the vibrations caused by the camera's mirror flipping out of the way.1) Am I risking any damage by tightening the forks tight enough so the camera doesn't weigh down the tube? 2) Is there a better way to hook up my digital SLR for pictures? 3) If the Lumicon is an okay way to go, can you recommend a good eyepiece, mostly for moon and planets? The largest one I can fit is the 15mm. I'd really like to use a 26mm, but it's too long for the adapter. Thanks in advance. P.S. I bought this at ScopeCity and was also looking to get the Lumicon UHC filter as well as it received a good review on your site. However the salesman said it would be a waste of money for the 105 as I couldn't expect to see much improvement. Your thoughts?
Go to the 2006 Canon DSLR Astrophotography Page.
Go to the 2005 Canon DSLR Astrophotography Page.
Go back to the Astrophotography Page.
Go back to my ETX Home Page.