Questions on the EQ6 for imaging

[DarkKnight]

Hi all,

Bought an HEQ5, it was faulty (won't go into the details) and returned it.

Have now ordered an EQ6, the vanilla version with the dual motors, (the price was right) hopefully arriving early next week. After a frustrating month with the HEQ5 I'm really looking forward to using something that actually works. I'm hoping the trade off for the extra weight (16kgs v 10kgs) will be more stability.

At this stage my main interest is terrestrial imaging, connecting a beautiful night sky to an interesting earth bound subject. My gear consists of a Nikon D800 and various lens from the Samyang 14mm f2.8 up to the Nikon 300mm f4 with 1.4 T/C.

From reading the forum I believe that I can get up to two minute subs with basic tracking, assuming that my mount is aligned and level.

Is there a way I can get into basic guiding without the expense of the GoTo upgrade kit?

I've read the PHD articles, looks good, found 'Shoestring' connectors and sundry other assorted hardware and software that, being very new to this astro genre, I don't really understand how they all tie together.

The other reason that I stepped up to the EQ6 was that knowing myself rather well, (you should achieve that familiarity in your declining years), I will probably want to get a modest 'scope somewhere down the track.

Any help for an old bloke with high aspirations and short pockets would be most appreciated.

Thanks

[ronin]

I can see one problem here:

You will be tracking the stars at sidereal rate as they "move", however with a chunk of the planet, or a tree in view that does not move it will appear to move as you are in effect tracking across a stationary object.

The resultant being a 2 minute exposure of a "stationary" set of stars but a 2 minute exposure of "moving" terrestrial objects.

If you have both in the exposure then at least one will appear to move.

[DarkKnight]

Cheers Ronin.

Yes, the procedure would involve blending a separate shot of the ground based part of the shot with the stacked sky.

[Knight of Clear Skies]

I believe you can guide with an EQ6 without using GOTO as the guiding port is on the mount itself. All guiding does is nudge the motors around a little so the implementation on the mount is very simple. Hopefully someone can confirm this.

[Zakalwe]

At this stage my main interest is terrestrial imaging, connecting a beautiful night sky to an interesting earth bound subject. My gear consists of a Nikon D800 and various lens from the Samyang 14mm f2.8 up to the Nikon 300mm f4 with 1.4 T/C.

Cheers Ronin.

Yes, the procedure would involve blending a separate shot of the ground based part of the shot with the stacked sky.

You probably don't need a tracking mount for this type of photography. Pretty much any sky image that includes terrestrial objects is, by it's very nature, wide-angle. You will be using very short focal lengths, otherwise you will not get any terrestrial objects in the field of view.

A good wide-angle lens (think in the region of 12-20mm), a DSLR, a solid camera tripod and an intervalometer is what you need. Have a look at the tutorials on lonelyspeck.com to see examples:

http://www.lonelyspeck.com/category/tutorials/

[DarkKnight]

After the debacle with the HEQ5 I suppose I should have waited till I received the mount, just to make sure it's not another weird spec Synta offering.

[DarkKnight]

Thanks Zakalwe.

I've had a play with the basic tripod set-up but want to go up a level, with sharper and brighter stars, and less noise.

[DarkKnight]

OK, my EQ6 has arrived with a few surprises. A BLACK mount and a WHITE tripod,  Huh ????, not a problem for me, looks quite smart,  and the tripod is the heavier 2" model.

Also missing were the counterweights and one mounting plate lock knob. A call to the dealer got some replacements sorted.

Now all I need is some sort of a plate to mount my camera gear on.

Being new to this stuff I'm still learning all the terminology so I don't really know what to look for. Most of the plates I've seen on the net don't seem to fit the profile of the head but then I'm probably not looking for the correct thing.

Here is a pic of the mount and I'd appreciate it if someone could tell me what type of plate fits it. The head has one vertical face and one slightly diagonal face whereas most of the plates I've seen seem to have both faces on a diagonal plane.

Thanks

[Zakalwe]

Vixen dovetail bar

[DarkKnight]

I'm obviously missing something here. The pic below is of a Lunt Vixen style dovetail plate, other brands seem the same.

The EQ6 mounting clamp has one vertical face and one sloping face, yet the plates all seem to have a slope on both clamping faces. Coming from a DSLR camera background, and using all Arca Swiss plates and clamps, it just doesn't seem very secure to me.

[Zakalwe]

The screws clamp directly onto the dovetail. It'll be fine for a camera and light load.

Aftermarket clamps are available which are a LOT more secure.

http://www.firstlightoptics.com/adm-replacement-saddles/adm-dual-saddle-upgrade-for-heq5-and-eq6-series-mounts.html

[DarkKnight]

I've gone for a Losmandy 4" plate and I'll look at doing indents where the lock knob screw heads meet the plate face to eliminate any slippage.

I'm no engineer but it seems like a pretty ordinary bit of designing where you only get part of the screw head making contact with the clamping face.

[ollypenrice]

It works OK. You can buy dual angled saddle plates but then you sometimes have to slide the dovetail into the clamp. This is not always easy if you're setting up on your own. The system you have allows you to set the saddle to horizontal with the angled side of the clamp at the bottom and the clamping screws at the top. Once you've set the dovetail into the clamp you can reach over the OTA to tighten the screws. It isn't idea for big taxing payloads but does work on more moderate ones.

One big thing to note, though. Your dovetail bar should have downward-protuding bolts at each end. Most are drilled and threaded in anticipation. These bring the dovetail to a halt should it start to slide through the clamp, as can happen. This really is supremely important.

Olly

[Zakalwe]

Don't crank the clamping screws until your forehead veins are bulging either.....the clamps are made of best Chinese monkey metal and can be split with over-enthusiastic force. A replacement saddle is a good buy if you are loading it up with a lot of weight, but for a camera and lens the standard will be fine.

[DarkKnight]

Thanks to Ollie and Zakalwe I've had a rethink, particularly about the plate length, and I've decided that I really do need the peace of mind that a longer plate with the facility to fit retaining screws gives.

To that end I've now ordered a replacement SkyWatcher saddle and Farpoint Bread Board Dovetail.

Thanks for the help guys. Most appreciated

[DarkKnight]

Only one of the two missing counterweights arrived today,  I wasn't surprised with that at all.

Anyway it gave me the chance to see how it all looked together.

Below is a quick pic of the whole set-up and another of my camera mount. The camera has a Wimberley Sidekick sitting in a Kirk monopod ball head, a perfect solution (I think) because the ball head drops to exactly 90°. With the Sidekick's up and down adjustment I believe this will assist greatly with aligning my camera to the mount. The camera is only 'tacked' onto the plate at present as I'm waiting for the correct socket head screws to arrive.

I think I can see a small glimmer of light at the end of the tunnel.

[beamer3.6m]

Very nice

[buikimaging]

What I'm wondering is: why is the camera not directly fitted to the mount and instead is first mounted on a Losmandy dovetail, then a camera mounting, then a vixen dovetail? Couldn't you just mount the camera with vixen dovetail directly to the mount?

You can mount 15kg scopes on a vixen dovetail bar so a camera and lens wouldn't be a problem. Could have save you a fair bit of money.

I don't know if you can track without GoTo as the Synscan handset turns on tracking. Also the counterweight is all the way down but I'm not sure if this is balanced at all. Is the camera really that heavy?

Do you have any pictures that you made so far?

[DarkKnight]

What I'm wondering is: why is the camera not directly fitted to the mount and instead is first mounted on a Losmandy dovetail, then a camera mounting, then a vixen dovetail? Couldn't you just mount the camera with vixen dovetail directly to the mount?

You can mount 15kg scopes on a vixen dovetail bar so a camera and lens wouldn't be a problem. Could have save you a fair bit of money.

I don't know if you can track without GoTo as the Synscan handset turns on tracking. Also the counterweight is all the way down but I'm not sure if this is balanced at all. Is the camera really that heavy?

Do you have any pictures that you made so far?

Hi,

The camera and lens, which weigh close to 4kgs, are mounted on a ball head via a Wimberley Sidekick, and then onto the Dovetail plate.

I chose to use the Sidekick because it gives me an easy way to adjust the vertical alignment of my camera to the mount. I already had the ball head and the Sidekick so I only had to buy the dovetail plate.

The counterweight was just fitted for the picture and sits a bit higher when balanced. I don't have any pictures yet as I'm waiting on the SynScan upgrade kit to arrive, hopefully in a fortnight.

Cheers

[Zakalwe]

There's no real need for the Sidekick-the mount itself will allow the camera to e pointed at any part of the sky. All you really need is a way to rotate the camera to frame the image.

Although you will be doing wide field, there's every reason to try to keep flex and wobbles to a minimum.

[Zakalwe]

There's no real need for the Sidekick-the mount itself will allow the camera to e pointed at any part of the sky. All you really need is a way to rotate the camera to frame the image.

Although you will be doing wide field, there's every reason to try to keep flex and wobbles to a minimum.

[DarkKnight]

It was more about fine tuning the alignment of the camera and the mount.

I guess I wasn't optimistic enough to think that I could attach the camera directly to the dovetail plate and have my sensor perfectly aligned with the mount.

[Zakalwe]

The alignment of the camera to the mount is virtually irrelevant....as long as the out is properly polar aligned and you can rotate the camera (ie in a tripod ring) then you will be good to go.

[wuthton]

Wow! Nobody is going to say that you've overloaded your mount. Make sure that you balance it though and you might need smaller (diy) weight.

[DarkKnight]

Wow! Nobody is going to say that you've overloaded your mount. Make sure that you balance it though and you might need smaller (diy) weight.

I've done a test balance and it balances with the 5kg weight about 1/2 way up the shaft.