Mandy D

I think that is a great choice for a first telescope. What are you thinking of photographing with it? For the Moon and bright planets, it will work well with your mobile phone. However, given that you are using a phone camera, you will only have a small sensor and with the focal length (1500 mm!) of that telescope you will not fit the Moon on the sensor, but you will be able to do close-ups. Deep sky is another game altogether and you will probably want to look at a proper astro-camera, but I'll leave that to others to discuss as I am not knowledgeable enough on that topic.

I have the AZ-EQ5-GT mount which has the Skywatcher 1.75" tripod and it has a different top to the 2" tripod which I believe is for the HEQ6 mount. The EQ6 has a larger diameter indent in the mounting plate on the tripod and I think the dowel is offset by more.

That's not too shabby for handheld to the eypiece. If it were displayed at 1:1 instead of being scaled by the website, it would be much better. I've just downloaded and viewed it at 600 x 702 on a 4k monitor and it looks fantastic.

I really should not encourage you, but I had to laugh at this one!

It looks like there are broken or missing teeth on the rack part of the rack & pinion focuser. Is that right? If the focuser is not moving out far enough to focus, you could try pulling the eyepiece out to compensate as a temporary fix. Another thought would be to disassemble the focuser and turn the rack around if that is possible so that you are using a good part of the rack. You can also buy lengths of rack gear in metal or nylon from engineering suppliers like RS Components, but you would need to measure the width, height and pitch to make sure you got the right thing. Other than that, it looks like you need a new focuser. Let us know what telescope you have and someone may have suggestions for the correct one or alternatives that might fit.

It all comes down to scaling once an image is cropped. I've noticed that this site tends to display small images at a larger scale. I think it is a CSS setting that is forcing small images to be scaled to fit the box on the web page. I, personally, find it annoying. Windows photo viewer displays small images with a 1:1 pixel matching for the screen, but scales large images that exceed screen size to fit, thus lower resolution. Cropping planetary images is vitally important to get them to display how you desire. To get them to display at the size you want on websites like this, you can always add a white (or grey, or any other colour) border around them to pad the space in the cell, once you have figured out approximately how big it is. Then, your black(ish) background appears at the size and scale you desire, if that makes sense. In my down to Earth photography, landscapes and the like, I always shoot at the maximum resolution and quality my DSLR is capable of, even if that means I will need to crop later. It keeps every possibility open right up to the moment editing decisions are made. I know of some professional photographers who claim to shoot at lower resolution / quality, because the best is not necessary, but I never really understand that. Digital zoom is a term I hate, as it gives completely the wrong impression to beginners. No zoom is involved, as you can see, it is merely cropping in camera and should simply be called digital cropping. Nice Jupiter image, by the way.

I beg to differ. The smaller sensor does not capture a larger image for a given focal length. The size of image projected onto the sensor is dependent only on the effective focal length of the optical system. Reducing the capture area of the sensor does not, in any way, change the image scale or number of pixels that the object of interest covers, hence no enlargement takes place. This equivalent to so-called "digital zoom" and is correctly known as cropping. I don't know of any modern DSLR which does not offer in camera cropping, but it is a pointless exersize anyway as none will crop to the sort of size needed in astro photography. In any case it will not enlarge the image. What matters is the pixel size and this where some astro cameras will beat a DSLR by having smaller pixels, hence an image of a given size covers more of them leading to greater resolution for a given focal length.

Line the box with 25mm extruded polystyrene insulation board available from home insulation suppliers. It is extremely tough, resiliant and lightweight. Easy to cut with a stanley knife.

It's not always straightforward to get uncompressed video from DSLRs (as you correctly indicate), but some professional cameras can do it another way. The Nikon D800 saves video files to CF or SD cards in MPEG 4 H.264 compressed format, but will output broadcast quality uncompressed video via it's integral HDMI port which can be recorded by commercial video recording equipment, but only when the cards are not present in the camera.

Be careful using video mode on a DSLR for planetary imaging, as the camera may be using downsampling, so although your image may cover a large number of pixels on the sensor, what the camera records to it's card is downsampled. The Nikon D800 uses a 32 x 18 mm section of it's 36 x 24 mm sensor for 1080p video. It's full resolution is 7360 x 4912, so this section of the sensor has 6542 x 3684 pixels and is downsampled to 1920 x 1080, a factor of 3.4. So, a Jupiter that sits across 200 pixels when shooting stills is going to be recorded at just 65 pixels. Is that what you want? It might be possible to Barlow much further in this mode, since it looks like you have bigger pixels (is that like binning? Not sure). I've found that with the D800 just shooting a lot of still frames works, but there is all the extra wear on the shutter mechanism, even in MUPpet (Mirror UP) mode. Regarding Barlows and focal extenders, I prefer the latter as the image is less distorted. OK, so you cannot manipulate the magnification with an FE like you can a Barlow, but you cannot have everything.

Now, if they did it in pink or purple, I could definitely go for one, purely on the aesthetics. It really looks the business: Would you mind telling us all a bit more about it, make, model, etc? Please.

Sorry to hear about this. I know this won't help recover the lost item, but what I would do, is get a lockable postbox and leave the key in the lock, telling them to unlock it, place the item inside, re-lock it then post the key in your letterbox or the post box. This is what I have.

If I ever build a new base for my 200P or 250PX, i'm taking inspiration from your design. BTW, I just noticed that Alice appears to be striking an Orion pose in your first image! With that red light, were you not tempted to drill a hole for Betelgeuse?

@PeterStudz that is a lovely set of photos. I like the height comparison between Alice and the 200P OTA! But, the illuminated base with Moon, Ursa Major and Orion is awesome!

@cajen2 They're still plugging the geocentric universe theory, then?

Photographed in Portugal, 2016 and combined into a single image.

Yeah, engineers assign those jobs to technicians! It could also confuse insects.

Does this count as a telescope? The Dragonfly Telephoto Array:

I was hoping that was a dial guage on the focusser, but it looks like it might a thermometer.

I know it's not yet completed, so maybe not a real contender, but the ELT is droolworthy. This picture, which compares it's size to the Ross Telescope (72 inch refractor) shows the sheer scale and beauty of it. Image used with permission, from https://elt.eso.org/public/images/eelt-rossetelescope/

OK, I didn't think it very likely, as it is not so common today, but the other imperial alternative is a Whitworth thread. 1/2" Whitworth has 12 TPI compared with 13 for UNC. The thread angle is 55° instead of 60° with UNC. For threads smaller than 1/2" UNC and Whitworth will screw together, despite the different thread form, but above this they will not due to differences in pitch. A third option that springs to mind is that it may be a metric fine pitch, which for M12 is likey to be 1.5 mm, instead of the usual 1.75 mm. This is sometimes found on vehicle fittings such as wheel nuts.

As usual, it was our elected representatives that got to vote on this, not us.

Are you sure this is a focus problem? If 25% are spot on and you have not touched the focus, then every image will be in focus. It sounds more likely that you have camera shake. Are you using a tripod and is it stiff and rigid with no movement? How do you release the shutter? You really do not want to touch the camera at all once it is on target and in focus. Use a remote release.

CERN appear to disagree with Sky at Night, giving an estimate of 27% for dark matter.

Now that's a telscope and a piece of art. It was what I had in mind when I read the OP. I'd definitely put one in my living room as a work of art. If only I had the money!