Longest Distance with S7??

You won't see it. Use a strong strobe light, triple prism holder and if the gun has a strength of return signal indicator use that to dial in.

One time we had to do a long shot down a power line. We only had a single prism with us. We wound up setting a nail somewhere near the middle of the line, and shooting the dist from BOTH ends. Essentially, it was a "Chaining Nail".
Or, you might JAVAD it!

N

I agree with Scott. Doubt you will see it. We sometimes use a hand mirror to flash the Instrument Man to get a sight on the location. The specs state:
Measurement range Prism mode
1 prism. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,500 m (8,202 ft) 1 prism Long Range mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,500 m (18,044 ft) (max. range)

I agree with Scott. Doubt you will see it. We sometimes use a hand mirror to flash the Instrument Man to get a sight on the location.
The specs state:
Measurement range Prism mode
1 prism. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,500 m (8,202 ft)
1 prism Long Range mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,500 m (18,044 ft) (max. range)
So it should be doable if you can get the gun to see it.

Scott Zelenak, post: 450639, member: 327 wrote: You won't see it. Use a strong strobe light, triple prism holder and if the gun has a strength of return signal indicator use that to dial in.

+1

The longest shot I took back in the day when I was in the field all the time was about 8,000 with a Set 3. I had to drape a florescent vest on the tripod to get in the general vicinity and move the cross hairs around until I got a return.

Scotland, post: 450644, member: 559 wrote: I agree with Scott. Doubt you will see it. We sometimes use a hand mirror to flash the Instrument Man to get a sight on the location.
The specs state:
Measurement range Prism mode
1 prism. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,500 m (8,202 ft)
1 prism Long Range mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,500 m (18,044 ft) (max. range)
So it should be doable if you can get the gun to see it.

I wonder how Long Range mode is engaged on an S7, I have never noticed it.
Maybe long pressing the Tracking/Std button?

Finelock/Activelock is only specced to 700m

One gallon plastic bucket, spray some orange paint over the bucket, cut a hole in the center of the lid and the bottom of the bucket, slide a 4 or 5' length of pipe the correct diameter for your mirror set, drill two sets of holes through the pipe and use them to plump the pipe with some wire strung through them hooked to some spikes in the ground, put the mirror or mirrors in the pipe on top of the bucket, you will see it easily if there are no heat waves.

If you have heat waves you may not see an airplane at 14,000'

Triple prism sets are for sale on ebay. I have one Ill never use.
N

standing on the corner, post: 450636, member: 8561 wrote: I need to make a 14,000' shot with an S7. I plan on using standard -30 mm prisms. Any tips or tricks that I might need to know? Should I plan on holding black cardboard behind the sight to be able to see anything?

TIA

I'm curious as to why you would need to make an almost 3 mile direct measurement. That seems like quite the task. What are the terrain and line of site conditions? Why not use GPS long static observations?

Yea what is the reason you need this shot? Just curious...

standing on the corner, post: 450636, member: 8561 wrote: I need to make a 14,000' shot with an S7. I plan on using standard -30 mm prisms. Any tips or tricks that I might need to know? Should I plan on holding black cardboard behind the sight to be able to see anything?

TIA

When I had a Geodimeter 4400, we tried to see how far we could measure with a single prism. At 4 miles, I told my helper to point the truck at me, turn on the high beams, and stand between the headlights. Yes, we got a bit over 4 miles to one prism and actually the headlights were hard to see (this was during the day). I was on a ridge that dropped off pretty fast and then it was very flat ground for miles. Between headlights during the day or if at night and not accessible by vehicle, a very bright light shining back to the instrument will help you get in the vicinity of the prism.

This long sight is for connecting the ends of a block by block (for 47 blocks) traverse on a coordinate system with known errors from east to west.

A GPS baseline converted to ground or mark to mark would get us close. But I still planning on trying this optically.

Completely unnecessary, but still fun to do I guess.

I agree you probably won't be able to see it. I would definitely recommend the triple prism, and it might help if you could do it at night. You could put a light on the rod to help it stand out.

Scott Zelenak is right: the ONLY way to see this at 14k feet is a strobe. I've tested a single magnified bicycle strobe light at 1/2 mile and it works great. Amazon has a gazillion of much much brighter disco strobes, including battery powered like this one:

https://www.amazon.com/Creative-Motion-Battery-Operated-Strobe-Light/dp/B0061XQDZG/ref=sr_1_10?s=musical-instruments&ie=UTF8&qid=1507845437&sr=1-10&keywords=strobe+light

You should see that through the scope without a problem. Whether the gun has the oomph to do the rest is another question.

I know its a silly question but gonna ask anyway. Does the autolock or finelock still work at such a distance?

Also wow, never imagined taking such a long shot before, maximum I took was 700m and could barely see it, I just turned roughly to it and let my Sokkia Robot auto lock unto the centre of the prism (which it did, thankfully)

Laser pointer from the prism, have them just keep wiggle it towards where they know the gun is from right above the prism. You'll see it in the scope if you have line of sight. Also, you can have the robot turn to the calculated position, should knock out a bunch of guesswork.

Ive done much further using blaze orange drums with headlights or good flashlights pointed at them. Needs to be twilight or dark but it works well. We did 15,300 with a triple on a tripod. We slipped a halfpipe of painted 12" pvc behind the target and hit it with a headlight. I tried foil but it was breezy and I ended up crumpling it and throwing it at my (laughing) rodman..

I have routinely taken shots in the past greater than 20,000 feet using a Wild DI-3000, mounted on a T-1600, to a single prism, but this has been from mountain top to mountain top, or across canyons, good to great atmospheric conditions. I seldom needed to use anything to enhance the visibility of the target, although a signal mirror flashing the prism, or heliotrope helped on occasion. I have seen the same DI-3000 shoot over 24,000 feet to a peanut prism, in less than ideal conditions. The longest distance I have ever shot was 38,485 feet in Montana, using an HP3820, and six prisms.
I do not know if that length of shot would be possible given your location, and the equipment you are using.
I have a Leica TC805 that I will shoot 15,000 feet to a single. Have done it numerous times recently from my home, to a mountain ridge nearly three miles to the south. Give it a try! Let us know how it turns out.