I'm trying to identify the source or tradition behind this anonymous 19th-century oil painting after Paul Delaroche's Napoleon at Fontainebleau.

I'm interested in identifying whether this variant corresponds to a known engraving, studio copy, academic exercise, or another source.

I've compared it with the familiar Lasalle lithograph and numerous online reproductions but haven't found another version matching these features.

# Technical details

* Oil on fine linen canvas.
* 71 × 89 cm (essentially a standard French Figure No. 30 format).
* Unsigned.
* Fine age craquelure throughout.
* Heavy oxidized natural resin varnish; appears never to have been cleaned.
* Lined onto an older grey-green flax/hemp secondary support.
* Mounted on what appears to be a handmade 19th-century keyed stretcher with hand-cut keys and irregular hand-forged tacks.
* No visible labels, stamps, inscriptions or collector's marks on the reverse.

# Composition

The painting is clearly based on Delaroche's Napoleon at Fontainebleau, but differs in several notable ways.

* The left half (especially the face and torso) is executed to a very high academic standard.
* The right half progressively transitions into simplified construction and ends with an intentionally sketch-like/non-finito right hand.
* A dark military-green/black oval masking form appears to be painted as an integral part of the composition rather than being a later addition.
* The background is essentially a black void.

# Differences from the familiar Lasalle lithograph

* The facial anatomy is not an exact copy; it appears independently modeled while remaining recognizably based on Delaroche's composition.
* The cloak closely follows Delaroche's drapery.
* The vest differs substantially, featuring five buttons and pockets, unlike the Lasalle lithograph. Some details seem closer to Delaroche's original painting, although arranged differently rather than copied exactly.

The painting has been in the same family since around 1970 (former USSR), but I don't have earlier documented provenance.

What I'm trying to find out

* Has anyone seen this specific variant before?
* Do the vest details correspond to another engraving or painted copy?
* Does the progressive transition from finished to unfinished resemble a known 19th-century academic teaching practice?
* Any art-historical leads would be greatly appreciated.

**Attached:**

* Overall image
* Face detail
* Vest detail
* Reverse
* Stretcher/corner construction

Research help identifying an unusual variant of Napoleon at Fontainebleau