FWIW ...

TELECONVERTERS. Some people hate them, some people love them ...

The results you get/achieve depend on the quality of the lens to which the teleconverter is attached BECAUSE (go figure!) a teleconverter is a magnifying lens ...

Personally, knowing the limitations AND that most lenses perform better when stopped down a 2-or-3 f-stops, I find the resultant image(s) generally satisfactory ...

So, I am in the camp that loves them despite the caveats ...

Recently, I 'discovered' that VIVITAR had come out with a 2x teleconverter (~10 years ago!) whose normally static tube also has a helicoid focusing mechanism ...

... What the heck, right?

So, I bought one!

The attached picture is a hand held snapshot which I took yesterday morning with the fore mentioned teleconverter + a plebeian 50mm f1.8 Olympus Zuiko lens using an m4/3 camera body; so, effectively a 200mm lens on a FF camera ...

... Wearing a jacket (it was only a little over 40ºF at the time & I was only wearing a T-shirt) and/or using a tripod would probably have helped a bit!

ZOOM LENSES. Sometime in the past few decades, Zoom lenses seem to have become the norm for most photographers. Plastic lenses & barrels have made them less unwieldy than in the past ...

Most of MY lenses are 'prime' (single focal length) lenses ...

I find that when I have occasion to use a Zoom lens that I have it racked the focusing ring to one extreme or the other ...

So, while it may be convenient to have only one lens semi-permanently attached to the camera body being used, if you know you will probably be using only ONE focal length, then buying a 'prime' lens will be very cost-effective ...

Particularly when one considers that there are numerous, vintage telephoto lenses which can be purchased for a fraction of the cost ...

AUTO-FOCUS. It seems that most UHHers have forgotten how to focus a lens ...

Regardless, I am apparently very old school because I would generally prefer to be able to focus on a specific object ...

... Oh sure, I can tell the camera where to concentrate its focus when using an auto-focusing lens ...

... but, since I don't have arthritis and I can see well enough to focus the lens, it's not a hassle for me to focus the lens.

........ I used to shoot a lot of "sports" photography when I was in college, so pre-focusing on a spot and/or following "action" is not difficult for me to do ... and, focusing on a static object is even easier!

YOU don't need to emulate the photographers who are on the sidelines of sporting events who have HUGE lenses which are owned by the organization for whom they are taking pictures ...

MAXIMUM APERTURE. When I used to shoot a lot of B&W film, the highest relative ISO I shot at was about ASA 1600 ... typically I exposed my Tri-X at ASA 320 (it's rated at ASA 400) when I wasn't shooting indoors in very-dim-by-today's-standards arenas; so, I tried to buy the fastest lenses which I could afford ...

... One of Leica's more recent additions to their line of lenses is a 75mm f1.25 Noctilux which retails for a whopping $12,000+ ...

Now, with ISO speeds approaching ridiculous numbers, it really doesn't matter how slow the lens is OR what f-stop is being used, IMO ...

All of the preceding is a long-way-of-saying that you could consider a manual focus telephoto lens EITHER in a Nikon mount OR even a pre-set lens with a T-Mount!

Why pay more?!?

BTW. If you aren't already using a tripod, you'll probably want to buy-and-use one.

(Download)

Gee ...

Based on your apparent attempt at pedantry with regard to the addition-or-lack of a hypen then I think that the majority of the users who have a DSLR should possibly classify-and-refer to their cameras as point-and-shoot cameras with-or-without-the-hypen UNLESS they are using a vintage, manual focus lens IF you are trying to eliminate extraneous descriptors ...

BTW. Clearly (!?!), IMO, the OP was trying to make a point that some of the benefits of a true mirrorless camera can be achieved with a person's current DSLR ...

Ergo, using/(i.e., image viewing ...) a DSLR sans mirror ... hence, his use of the hyphenated "mirror-less" instead of "mirrorless."

Several decades ago I needed/wanted to make some Kodachrome slides of some existing work (so, it was essentially the situation as for the copies you want to produce) ...

The house I was renting had an open, south facing porch on which I could set up my "artwork" (... leaned against the back of a simple lawn chair (!), so the flat surface was at about the angle of a music stand easel) and camera (facing south at the same angle ... I used a 90mm-180mm Macro zoom lens to ensure a rectilinear, flat field because the originals were smaller than 11x14 (of course, a 50mm-60mm Macro lens would probably be more suitable for larger originals) + to make framing easier on multiple images which varied slightly in size) ... essentially, providing "northern light" (of course, you would want a south facing porch OR one of the equivalent suggestions already made to provide indirect natural light) ...

IMO, the color balance was perfectly neutral.

FWIW ...

Several decades ago I needed/wanted to make some Kodachrome slides of some existing work ...

The house I was renting had an open, south facing porch on which I could set up my "artwork" (... leaned against the back of a simple lawn chair (!), so the flat surface was at about the angle of a music stand easel) and camera (facing south at the same angle) ... I used a 90-180 Macro zoom lens to ensure a rectilinear, flat field (originals were smaller than 11x14 ... the slightly longer focal length allowed for some distance between the camera and the object ... a regular 50mm-or-60mm Macro lens will possibly work better for larger surfaces) + to make framing easier on multiple images which varied slightly in size) ... essentially, providing "northern light" ...

IMO, the color balance was perfectly neutral.

I think you may want to reconsider the capabilities of your "new" camera, because ...

There is "no free lunch" when shooting in compromised lighting situations ...

If-and-when you use a higher ISO then you will typically get a less satisfactory image than when shooting at (for example) 100 ISO ...

And, I would classify the lighting in the sample you included as being compromised.

With THAT in mind, you may want to consider shooting the same scene with BOTH cameras at the same time at the same ISO/etc. so that you can achieve a better assessment of the "new" camera's capabilities-or-deficiencies.

Unless the map is in a hallway, then I believe that Bobspez's suggestion is better than stitching multiple images together ...

A 50mm lens on a FF camera can be used if you can be ~12 feet away from the wall on which the map is hanging.

To state what is hopefully unnecessary:

Use a tripod + consider using a level (for the tripod head) to ensure the final image is square if your viewfinder does not have grid lines to assist you.

BTW. I have successfully stitched a simple map together which was comprised of two image using the very primitive MS PAINT program which has been included with all versions of WINDOWS ... so, that means that if you are familiar with almost PP program then you should be able to stitch a multiple image map together as long as your original image(s) are well planned so that the adjoining edges are the same dimension ...

You can practice on images taken of a "red brick" wall from the distance at which you anticipate that you will be taking the images of the map to hone your skill level with your camera & possible PP (if you are stitching the image).

CONSIDER ...

Choosing the LENS, first ...

And then, the camera body.

With THAT said (based on only the TWO choices which you have indicated), I would choose a NIKON mount lens-or-lenses -- either a current FX lens (full frame) or a vintage manual lens ...

You do NOT need to use a Nikon body to use a Nikon mount lens ...

Almost ALL Nikon lenses of almost any vintage will fit on current Nikon FX & DX digital camera bodies ... the same cannot be said for Canon lenses and Canon digital camera bodies.

While you generally DO need a Canon body to use a Canon lens, I think there is a Canon-to-SONY adapter (if you want a full frame alternative to a Canon digital camera body) ...

So, consider the Nikon/Nikkor lens(es) + a MIRRORLESS camera body with an EVF (electronic view finder) -- either an m4/3 (if a full frame is not necessary) body or a SONY (if you feel a need for a full frame sensor) body.

You can opt for a DSLR, but they will be larger & heavier AND the debate between optical viewing & electronic viewing is ongoing and may be worth considering.

BTW. In body stabilization is a good thing, but not always necessary (particularly, if you are inclined to using a tripod).

Without reading all the replies (so, this might be an echo) ...

YOU can restore your WIN8-or-WIN10 (and, probably some earlier versions) to "factory specs" with a few key strokes ...

You'll have to look up the how-to process ...

It's painless EXCEPT for needing to re-install your OTHER software ...

BTW. Under your particular circumstances, you'll probably want to revert to a "factory spec" computer whether-or-not you install LINUX on it.

Good luck!

OKAY ...

I cannot speak to the aperture ring on digital Nikon lenses ....

And, I certainly cannot invalidate what YOU did to make your older Nikkor lens viable on your digital Nikon camera body ...

The OP was simply asking about converting non-AI to AI (vs. later iterations) for use on a Nikon Df body ...

And, that was the raison d'être for my reply as presented.

Comprendez-vous?

FWIW. I will confirm that Schott glass covers are very vulnerable to cracking ...

Mine did, too!

While the LCD surface may be scratch-resistant, they can be scratched, so I am in the camp that believes that SOME protection is better than none ....

And so, the thin, inexpensive, press-on protectors which are used for phones-and-tablets are a-good-thing to consider.

I have related MY experience ...

AND, I have also related MY observation of MY AI-indexed lenses (most ARE Nikkor).

The aperture ring on subsequent Nikkor lenses may indeed be different; but, the OP's lens is an older lens whose aperture ring certainly had the SAME outer diameter as the one which I amended since THAT DIMENSION was standardized because of the indexing prong ...

N'est-çe pas?

Back in the day, the recommendation was to send the lens to EPOI (Ehrenreich Photo) ... at the time, I think the fee was ~$20 plus postage-to-send-it-to-them ...

I suppose that the easiest way to convert the lens is to send it to Nikon ... the fee is certainly more than $20, now.

Because I had the misfortune to buy a new non-AI lens just a few months before the change to AI "coupling" was introduced I opted a DIY "fix" (the "fix" worked on a subsequent FM body which I eventually got which must have been the reason that I bothered to "fix" the lens) ...

If you look at a non-AI lens and an AI lens, you will see that the difference is the perforated indexing prong (to allow some light to fall onto the aperture ring) PLUS a supplemental partial collar on the back edge of the aperture ring; so, you simply need to add a supplemental collar to the aperture ring.

For reasons which I no longer recall, I had an M42 lens mount ring whose inner diameter matched the outer diameter of the particular lens (90mm Vivitar Series 1) which I wanted to modify ...

So, I simply cut a portion of the M42 lens mount ring to "glue" onto the aperture ring (BTW ... after looking at an AI-indexed lens that I had, I believe that I deduced that the one edge should index to f5.6) ...

Armed with the presumption that the indexing collar should mimic the location on a "real" AI-indexed lens, I removed some of the anodization for the edge of the aperture ring (tape the portion which you want to protect!) and then epoxied the partial collar in place.

24+ hours later, I (spray) painted the add-on collar (again, tape the portion(s) which you want to protect!!) ...

DONE!

I have (and, have used) Macro lenses, bellows, extension tubes, and close-up lenses ...

BUT, I don't do what many consider to be Macro photography ...

So, what I say is based on my just wanting to get a little closer to the subject.

With extension tubes, if you have a FLAT FIELD lens which your Tokina lens should be, then you should not expect any distortion ...

IMO, this is ONLY a factor if you are photographing objects which clearly have perpendicular lines -- e.g., stamps.

With close-up lenses, you may-or-may-not realize some barrel distortion or pin cushioning -- it REALLY depends on the lens ...

I was very skeptical (aka "snobbish") about close-up lenses; but, I wanted to see if I could get closer to an object while using a fixed-lens TLR. The lens was a 75mm f3.5 Tessar formula. I think I probably stopped it down to f5.6, maybe f8.0. I thought the results were excellent; but, THAT was contingent on my taking the time to focus carefully on the object.

IMO, if you are not trying to capture the image of a FLAT object, then it really doesn't matter if you opt for close-up lenses because the edges will not be in focus and the distortion will be minimal.

The huge advantage of using close-up lenses is that your autofocus will still function ... but, you should probably be focusing in manual mode.

On the other hand, the lens's autofocus will not function with "dumb" hollow extension tubes or a set of bellows; so unless you pony up for tubes with communication pins your camera will not communicate with your lens ... again, you should probably be focusing in manual mode.

So, just exactly what types of objects were you planning on taking MACRO images of?

Stamps?

Coins?

Flowers?

Bugs?

Other?

BTW. I eventually opted to mount a 105mm "enlarger" lens on my bellows rather than trying to use the bellows with any of my other lenses.

Using a tripod will allow an individual to test the lens's capabilities sans any possible interference (i.e., camera shake and/or poor focusing) by the user ...

AFTER one is convinced that a particular lens has-or-lacks a certain IQ level, then s/he can proceed, accordingly ...

Subsequently, the individual can take pics WITH-or-WITHOUT a tripod with the fore knowledge of what the particular lens(es) will be capable of yielding; and, the possibility of a less than satisfactory image may not be due to what the lens is capable of providing.

On the other hand, I've got ONE lens which will not benefit greatly from my using a tripod; and, I would say that the particular lens can be best used to simulate DIANA-like photographic images (yes, that is apparently a genre!?!) when it is attached to any digital camera body!

FWIW ...

NOT all lenses are created equal ...

I do NOT know the optical capabilities of any of your lenses ...

I know that some of MY vintage lenses of the same focal length are better than some others ...

Similarly, I just read in a recent UHH thread that a 24mm f1.4 Samyang lens is (according to the poster) sharper than his vintage 24mm f2.0 AI Nikkor lens!

Is that true? I don't know.

Regardless, I think that BEFORE you pony up for a new camera + new lenses that you buy a simple LENS ADAPTER (IF NECESSARY!?!) which will allow you to install your friend's lens on your camera body ...

And with a tripod (if you don't have one, then buy-or-borrow one), do some actual tests to see if the difference in the quality of the images is due to the lens(es) which you are using AND/OR if it is due to YOUR (in-)ability to manually focus your vintage Minolta lenses as well as they can be focused ...

An unsteady camera can go a long way toward lessening a lens-and-camera's capabilities.